Here's a file from early 2013 that had input from many players for certain characters regarding a "MK9 Dream Balance Patch": (KEEP IN MIND THIS STUFF IS FROM A LONG TIME AGO WHEN THE GAME WAS HOT)
GENERAL CHANGES (MUST HAPPEN AND ARE MOST IMPORTANT):
- Input bug and wonky precision drops are now completely smoothed out and fixed
- Specific stages that lag and slow the game down with certain specials or variables in play are now neutralized
- Random block advantage bug on certain frames for some attacks against the defender is now removed and blocking is 100% consistent at all times
- Player 1 Advantage no longer exists and both players can now trade
- Meter Drain bug when performing a move that requires super meter or an X-Ray is now completely fixed and no longer an issue
- Air Breakers no longer give the player who broke massive frame advantage and free offense opportunity
- The overall negative edge and excessive input storing is now slightly reduced across the board
CHARACTER SPECIFIC CHANGES:
1.)
Kabal
- All Gas Blasts now do 4% damage
- Can no longer cancel EX Nomad Dash
- Saw Blade hitbox is no longer active while behind Kabal
- F+4 no longer restands an airborne opponent
2.)
Kenshi
- EX Spirit Charge is now neutral on block.
- EX Rising Karma is now full combo punishable on block.
- EX Rising Karma now has reduced pushback on block.
- Normal Spirit Charge is now a high and can be ducked without crouch blocking
3.)
Cyrax
- Command Grab hit advantage reduced so it no longer gives a safe jump on hit.
- Net can only be used once per combo.
4.)
Sonya Blade
- EX Cartwheel is now full combo punishable on block.
- Dive kick has more recovery on block.
- Military Stance F+1 is now -1 on block.
5.)
Johnny Cage
- F+3 is now always -2 on block.
- F+3,3,B+3 is now always -5 on block.
- Regular nut punch no longer gives a safe jump on hit.
- EX Straight Forceballs are now +1 on block.
- The second part of EX Flip Kick now only comes out on hit.
6.)
Kung Lao
- Regular spin no longer has invincibility on wake-up.
- Teleport 3 can no longer link into normal attacks or combo strings when it is blocked.
- EX Teleport into delayed 1 no longer gives Kung Lao extra super armor frames.
- Teleport 2 now has an increased hitbox to prevent it from being low profiled easily.
7.)
Freddy Krueger
- Both EX Teleports now have more recovery on whiff.
- All versions of ground Spikes now do 1% chip on block.
- EX Ground Spikes now has increased damage scaling.
8.)
Smoke
- Being able to special cancel off of F+4 is now removed.
- Smoke Bomb is now -12 on block.
9.)
Kitana
- F+2,1 launcher is now -5 on block.
- Increased damage scaling on ground fans and air fans.
- Cutter is now +15 on hit and no longer gives a safe jump.
- Pretty kick now gives a safe jump on hit.
- The second hit of EX Pretty Kick is now a mid.
- Double Ground fan is no longer auto blockable on hit from full screen.
10.)
Skarlet
- EX Double Daggers cancel is now +15 on block to prevent 50% chip block string trap.
- Teleport now has a slightly improved hitbox to make it connect against an opponent more consistently.
11.)
Shang Tsung
- Close Ground Skull is now neutral on block.
- Far Ground Skull is now +4 on block.
- The second hit of Soul Steal is now unblockable.
- Both hits of Soul Steal have now been reduced to inflicting 4% damage each.
12.)
Liu Kang
- B+3,1,2 is now -3 on block.
- Dragon Stance+3 overhead now makes Liu Kang enter wake-up mode on whiff and block.
- Dragon Stance+2 is now neutral on block.
13.)
Jax
- F+4,1,3 is now always -5 on block.
- F+4,1,4 is now neutral on block.
- The last hit of 2,F+2,B+1 now has less recovery on hit to allow juggles.
- EX Ground Pound no longer pops the opponent up after an OTG for a full juggle opportunity in the corner.
14.)
Reptile
- Elbow dash has more recovery on block. (Same principle as the Sonya Dive Kick nerf)
- 3,2,B+4 now makes Reptile enter wake-up mode on whiff and block.
15.)
Raiden
- EX Vicinity Blast is now a true mid like Johnny Cage’s F+3.
- EX Vicinity Blast is now advantage on block.
16.)
Sektor
- The second hit of 1,2,B+1 is now extended so it never whiffs if the first hit connects on hit or block.
- F+2,B+1 string is now -6 on block.
- D+1 is now advantage on hit.
- EX Flame Thrower now has armor.
17.)
Mileena
- EX Neckbite now has armor.
- D+1 is now advantage on hit.
- Tele Kick input now changed to D,D+3+4 to prevent it from ever coming out by accident.
18.)
Rain
- D+3 now has slightly better recovery on whiff and block.
- D+3 is now advantage on hit.
- Rain can now block during H2O Buff but damage bonus is slightly reduced.
- Water Bubble projectile now hits mid.
19.)
Baraka
- U+4 now makes Baraka enter wake-up mode on whiff and block.
- U+4 now does 12% damage on hit.
- The last hit of B+3,1,F+1 is now +1 on block.
- The last hit of 1,2,2 is now an Overhead.
- EX Chop Chops now has armor.
20.)
Ermac
- D+3 is now advantage on hit.
- You can now special cancel off of U+4.
- EX Choke now has armor.
21.)
Sub-Zero
- Standing 2 is now a true mid on every character like Johnny Cage’s F+3.
- F+4,1+2 string is now -6 on block.
- The beginning animation frames of Ice Puddle can now be cancelled by performing another special move before the hitbox becomes active.
- The beginning animation frames of EX Ice Puddle can now be cancelled by dashing forwards or backwards before the hitbox becomes active.
22.)
Noob Saibot
- D+1 now has 6 frames of start up.
- All versions of portals stay out one second longer.
- EX Low Shadow Slide is now safe on block.
- EX Overhead Shadow is now safe on block and has more advantage on hit.
- EX Teleport now has armor.
- Ghost Ball now has significantly better recovery and is slightly faster on start up.
- Ghost Ball can no longer be reflected and is now immune to parry projectile type based attacks.
- X-Ray now has slightly longer duration of armor frames.
23.)
Scorpion
- D+1 is now advantage on hit.
- D+3 is now advantage on hit.
- D+4 is now advantage on hit.
- 2,1+2 string is now -5 on block.
- F+2,1,4 string is now -2 on block and can now be cancelled into specials.
- Spear now has reduced recovery when blocked.
24.)
Sindel
- Hair Whip is now a true mid like Johnny Cage’s F+3.
- EX Hair Whip now has armor.
- U+4 is now faster and has an improved hitbox.
- You can now cancel into air close and far air fireball when doing U+3.
- AIR EX Fireballs now hit overhead.
- EX Straight Fireball now has pushback on block.
- EX Low Fireball now has pushback on block.
- The last hit of 4,4,U+3 now comes out on whiff and block.
- The last hit of 2,1,2 can now be dash cancelled out of when the 2 is held down.
- Sindel can now enter Levitation mode when she’s at the peak of her jump.
- The recovery when air backdashing while in Levitate is now reduced.
25.)
Quan Chi
- D+1 now has 6 frames of start up.
- All versions of Ground Burst now hit Low.
- All versions of Ground Burst are now -7 on block.
- EX Rune now does 3% on hit.
- Skeletal Boost can now be activated during Trance.
- The last hit of 2,1,U+3 string can now be special cancelled out of.
26.)
Nightwolf
- D+1 is now advantage on hit.
- F+2 now hits overhead.
- F+3 now hits low.
- 2,3,4 string is now +5 on block.
- The second hit of EX Hatchet Swipe is now an overhead and +5 on block.
- Lightning Strike now has slightly better recovery on whiff.
27.)
Cyber Sub-Zero
- D+4 is now advantage on hit.
- Teleport now has some invincibility frames similar to Cyrax’s teleport.
- Ice Ball now hits mid.
- EX slide now has armor.
- Close dive kick has slightly less recovery frames. (similar to Kung Lao’s Dive Kick).
- All versions of ice bombs now have reduced recovery.
- Can now perform air close dive kick or air far dive kick during the second attack of B+3,2 string on block or whiff.
- F+1,4 now makes Cyber Sub-Zero enter wake up mode on whiff and block.
- X-Ray on block no longer causes Cyber Sub Zero to roll up in a ball punish animation, he now lands next to the opponent at +1.
28.)
Jade
- EX Glow now starts up on the first possible frame so it cannot be stuffed.
- All versions of boomerangs now have improved recovery.
- The second hit of EX Up boomerang now hits overhead on the way down.
- U+3 now hits mid.
- The last hit of 1,2,2 is now -5 on block.
- The last hit of B+1,F+1 is now neutral on block.
- The last hit of B+1,F+1 now comes out on whiff.
- The second hit of 3,4 now comes out on whiff.
- 1,2 now combos into Overhead Staff Slam on hit.
- 2,3 now combos into Overhead Staff Slam on hit.
29.)
Stryker
- Low Grenade Toss now has improved recovery.
- Low Grenade Toss now has pushback on block.
- High Grenade Toss now has improved recovery.
- High Grenade Toss now has pushback on block.
- EX Grenade Toss now has armor like Kenshi's EX Tele-Beatdown.
- The last hit of 2,3,2 can now be cancelled into specials.
- Baton Sweep is now -6 on block.
- X-Ray now hits Overhead to prevent whiffing issues on certain characters.
30.)
Sheeva
- D+3 now has slightly increased cancel advantage.
- EX Teleport now has armor on the entire duration until she hits the ground.
- D,B+4 Ground Stomp can now be cancelled into other special attacks before the hitbox becomes active.
- EX D,B+4 Ground Stomp can now be cancelled by dashing forwards or backwards before the hitbox becomes active.
- EX D,B+4 now OTGs and goes through wake-up invincibility.
- The last hit of 1,B+2,F+1 is now +1 on block.
- F+4 is now -2 on block.
- Fireball hitbox slightly increased so it can no longer be low profiled by any character.
- F+2 is now much faster.
- EX Low Command grab now slightly moves Sheeva forward.
- The last hit of B+1,2,1+2 is now +1 on block.
- The last hit of 2,1,2,F+1 string can now longer be low profiled by any character.
- The last hit of the string 3,3 now restands an airborne opponent similar to Kabal’s F+4 animation.
31.)
Kano
- Choke is now a mid.
- B+1,1,2 no longer has a gap between hits on block.
- B+1,2 now gives a safe jump on hit.
- B+2 is now slightly faster.
- F+4 is now faster.
- The second hit of EX Up Ball now has significantly reduced recovery on whiff during landing frames.
- Horizontal Kano Ball input now changed to B,F+3.
- EX Knife Toss is now +1 on block.
- X-Ray now has an increased hitbox so it can no longer be low profiled by any attack.
Hope you can implement some of these changes. MK9 really didn´t need that many drastic changes for characters as much as it did for the core system changes that needed to be addressed.