excellent
this is a very good game, it got me playing for quite a while and it still is
here is my opinion:
pros:
-i like the strategy, shoot em up and lvl up system put together
-each fighter had their strong and weak points, actually every of them can be deadly when properly used.
-there was some high difficulty which i like, tough difficulty setting would be nice
cons:
-lvl up system is like everyone said flawed, it takes way too much time to lvl up violetta, but you can lvl up so quickly with sammy.
-sometimes, there are way too many rocks on the stage, i know it's good to grind up super shoot attack, but it gets really annoying when you can't even hit your enemy because the screen is full of them.
I just defeated the second boss, and as a response to azaelwanderer's nice review: i do agree that violetta is very slow, but if you manage to get her super shoot, it deals some insane damage, and max is actually an excellent character if used properly, he is quite deadly on down shooting enemies as his shoots spread around the screen he can get them from anywhere, and also, if you're close enough to the enemy, you can hit with 3 shoots, even all of them if good enough. and the special is deadly too, as you need not to be vulnerable to enemies attacks to do lot of damage.
Here is, imo, the best characters in order (by considering they are the same lvl):
-Hexos
-Sammy
-Rufus
-Zero
-maximillion
-Vanilla
-violetta
-lovett
hope that review pretty much helps you out on your next version of the game.