The controls ruined the game completely. UTTERLY. What a piece of shit control system. Go have a look at Guitar Hero to understand why they laid it out like they did.
There's quite a bit of trouble with this. Namely the fact that mana increases do nothing useful (making a pure magic or similar to that build useless in terms of growth), revenge waves can be absolutely ridiculous (as is hero downtime) and there's not enough information on each of the creature stats. I mean, how the hell was I meant to know PIXIES are god damn healers? The most useful units in the game... And it doesn't tell you they are?
I think what many of the people rating this badly aren't getting is that it isn't a strategy game, but more of a puzzle game. You have to find the "correct" combination to get to the next stage, essentially. Strategy requires... Strategy.
A couple've negatives: There is no "catch up" system for when certain party members are of a massively lower level than everyone else. It really needs one of these, even if it is just getting the experience per kill that non-killers get.
I've also noticed you're sort of weak in terms of boss design. They're very repetitive and don't really require much thinking. Go have a look at Sonny's final bosses (which are, despite that games poor quality, very good in terms of creative thinking) for an example of a "good boss fight".
A personal pet peeve: I do wish armour would change like weapons do. I love that.
Other than that, it's a lovely game. If it was a commercial RPG, I would've given it 4-4.5/5, but as it's a flash game... 5/5. Hope to see more in the near future, it might even win you some more monthly cash prizes. =p
Sadly, this isn't THAT useful. AS an example, the shadow temple bit could've really done with a map (as could have the Sand Caves, I suppose) so players could find their way around. Maps all around would've been nice, actually, along with a list of the items that provide characters with abilities.
I prefer SCGMD2 to this, simply for the Amateur / Pro selection, the way the guy did what you did during the song and the way the songs didn't fade out.