I love me some Ashura. He plays really well! A simple moveset, but one that's still effective in maintaining smooth gameplay! Although I feel like his physics could be altered to further differentiate him from Sonic, he's still fun to play; perhaps give him a hint of ice physics, not full-blown slipperiness, but something that'd throw a player off at first and take some time to get used to, BUT, if mastered correctly can be used to blitz through levels with the added "slippery momentum" along with the drop dash (a la Shadow to some extent) - with these ideas in mind, perhaps having the double jump abilities and drop dash be dependent on momentum would also encourage riskier play. I see very good potential with this character, and I'll be eagerly seeing what you'll do next!