honestly after playing the crap out of grundy. i think i can give out some good feed back to make him better if my suggestions are taken seriously. his character flaw is very exploitable imo.
here are some things that i can say will make fair/solid and better in general without overpowering him;
-trait grabx1 as a starter (not combo'ed into trait) should not be clashable, however it should be clashable if grundy does trait grabx2.
reason for this suggestion is there is so many throw immune strings, specials, zoners etc that getting a trait grab against a good player doesnt happen that often in a match. this change would be great especially against hard zoners the reason why this is good, players would use defense chainx1 more often in midscreen to keep the opponent near grundy vs having them away from you which you DONT want to do since grundy exceeds better up close. i think this is fair, right now pain chain trait itself doesnt get clash and does 9%, but with one more followup would help grundy a whole lot more without the fear of a clash which powerx1 18%/healthx1 16%/defense chainx1 14%
-grundy's standing 3 isnt that great(perhaps one of his worst normal moves). it doesnt lead to much by itself and i dont understand why its -2 on block. this move should be buffed to +2~3 on block so that he can keep some pressure against opponents. as we all know his starting bnb is 12 frame startup, so this change can be a great help to his gamestyle/pressure. on hit i recommend having the opponent lift into the air a tad bit higher making d2 easier to hit in the corner. sure 3,2 launches the opponent already but if you commit to it you will be at -1 on block. at least with hit confirming with just 3 will make things alot better for more experienced players
-grundys 3,3 is also not that good.i recommend making the second part come out 1 frame faster, right now its punishable by 8 frame moves. you could also back dash it, super or armor it. so making it a frame faster isnt asking too much. also on block the push back is too much. by reducing the pushback a tad bit from a block 3,3 it would help grundys mid game so other moves can actually reach them so you can followup with more stuff.. whats the point of having +12 block advantage if you cant even hit them midscreen? lol
-a missed command throw with grundy hurts alot compare to other grapples/command throwers. so what happens is people try to exploit this by just jumping immediately after doing anything, i say reducing the recovery frames by 5~7 (currently at 30)frames less will help if opponent doesnt react to a full combo properly. as we all know it takes a good read too know when to grab. and even then throw immune strings are a annoyance to grundy players which opponents are gonna exploit so they cant get thrown which is bs imo.
thats a few suggestions i got. feel free to throw some feedback why you think some things seem to strong or not worth changing. overall his gameplay will still stay the same. zoners still gonna try keeping him out and what not.