Nice to see some more original spritework making its way into projects lately. I can't comment on much else since I haven't seen Superjail, but it's looking really good regardless.
Don't worry about beta testing just yet. Try to come up with a comprehensive gameplan first. Will it be a grappler? A rushdown character? A keepaway character? Keep these in mind and come up with a moveset that complements these choices.
When you get that down, you can worry about things like what gameplay style it will have, how many buttons, etc. Some of these things will change, but its general gameplan will probably remain the same. I'm glad to discuss various gameplay aspects if necessary, just don't ask me for coding help because I can't code at all.
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