Interesting Idea
Your instructions were a bit inclear. I didn't realize what the active bar was in the beginning. I thought it was just the health for both characters rising before the fight started, and it took a bit of time to understand how the special attacks worked.
I understand that this is just sort of a survey to see what people think though, so that's fine for now. I'm not exactly sure what you're expecting the final product to be, but the idea seems sort of interesting. If by improvements you just meant adding more different types of combos, making it longer, and all that stuff, that just won't cut it. At the moment the combat is just I attack you, you attack me. There has to be a bit more strategy involved than that. Sure, there's the special attacks, but that's just a simple math calculation. Find how much damage each does, divide it by the SP is consumes, and then keep using the attack that has the higher result.
Good luck with your game.