You really want to pay $60+ for all them?
How much were the DLC characters in MK9? $5 per character, or $15 for 4. So if we have 18 characters as DLC, you are looking at $90 for all the characters individually, or probably $60 for all the bundles. That's ridiculous.
Other things to consider, if you know how game design works...
It takes money to create these things. So they need to make a good enough profit to make it worth it, You put out 6 DLC characters, for a reasonable price such as $20, people are likely to buy them. Because the 6 chosen, will be popular picks that people will likely want. And if people like the game, they'll be willing to fork over a little more to obtain it. Here's the problem. 18 characters, is a huge gamble on turning a profit. Asking your fans to pay $60-$90 extra, is a huge difference than $20-$30 extra. Also, the characters start becoming less popular and "must have" the more you start to try and offer. Remember, to turn a profit, you have to offer characters that appeal to ALL audiences, not just niche fanbases of super hardcore comic book fans. Most characters worth paying for that appeal to the masses, are already in the game. I can think of 6 for sure sellers that aren't. I can't think of 18. Let's look at your list:
**mmh
fire storm
zatana
**brainiac
**general zod
captain cold
metalo
**bizzaro
medusa
**red torando
captain atom
green lantern john stewart
statick shock
blue beetle
**redhood/jason todd
black hand
atrocitus
killer frost
From your list of 18, I highlighted the ones that actually MIGHT appeal to the general audiences. Mostly because of their appearance in a film, animated film, or are relevant enough to be known outside of comic book readers. The exclusion being Red Tornado, and I will get to that.
The rest, aren't known well enough, by look nor by name(Capatin Atom, Medusa, Zatanna, Firestorm etc.) to garner any real hype, or that "must have" feel, enough to warrant shelling out $5 for one. As well as some being too similar to what we already have(Atrocitus, John Stewart, Static Shock etc.), we already have 2 lanterns, and 2 electricity users, John is better suited as an alt. skin.
Now, of the 6 that are actually plausible to sell well, we have:
Martian Manhunter
Brainiac
Zod
Bizarro
Red Tornado
Red Hood
I included Red Tornado, because he actually has the look, a cool name, and the abilities to warrant DIFFERENT gameplay. Martian Manhunter is similar in reasoning, and his fanbase is a little less niche. However, the rest, are based purely on their appearances in either the upcoming Superman: Man of Steel(Zod) or Superman: Unbound animated movie(Brainiac), or their appearances in past films or animated movies. They could potentially sell. You HAVE to pick people who will sell enough to warrant the time, money, and effort put into them. Unless someone is a HUGE comic book fan, to know all these characters, and likes them enough, and has money to just throw around...most people aren't going to pay $5 each for the rest of the people up there, or over $60 for the lot. You may pay for them, but your average consumer doesn't care enough about most of those characters, known them, or want to waste their money after dropping $65 on the game itself. That's not a good business move.
Now, that's where we get to the next reasoning. TIME. It takes TIME to make these. You have to discuss who you want, then make concept art, then make models, then motion capture moves, then animate, then render, then write and create endings, and then test to work out any bugs/glitches. It takes time to do these things. 4 characters? My guess would be approx. 2 months. 18? We're talking approx. 8-10 months. Guess what? They have another game to make as soon as they are done with this current one. MK10 is sure to come in the next 3 years, and they can't be dedicating time and man power to a game that's already finished. They need to move on at some point.
My last point, is simply, from our end of things...gameplay. Right now, the 22 characters shown off, look awesome. They have put a ton of work in, and chose the right characters to ensure everyone looks/feels great and plays differently than the rest. Right now, they are putting in a ton of hours trying to polish things off and ensure it is as balanced as possible, so no one character gets left out, or too powerful. That's not easy, and is a constant process even after the game's release. With a likely roster of 24-26, that's no easy task. Now, add 18 characters to that. Now, all of a sudden, characters don't feel so unique anymore, you start having characters that feel/play too similar, and the even bigger issue, things get unbalanced that much easier. The more options you give, the harder it is to keep organized. It was a continuous struggle to fix things and keep things as balanced as possible in MK9 with 32 people after DLC, and you want them to do it with 42 characters?! Gameplay is going to SUFFER.
You can't just say "man, put more characters in, more characters in, more characters in!" and expect the same quality, attention to detail, and overall balanced gameplay with 42 characters, as you would with 32. It just doesn't work like that. It requires the phrase "Less is more".
A 24-26 character roster at launch is great. With 4-8 DLC characters to follow being a decent addition, with 6 being the ideal number. I can think of 6 that will sell to the masses, turn a profit, add unique gameplay, and managable to keep balance.
Remember, less is more. Gotta save some for next game.
Please read my long ass response, because it will help you understand just why that's wrong.
