Come on! man
I definitely appreciate the time spent on sprite accuracy and AI. A big improvement from the last game. However, I've found that my only strategy to getting through the levels is by ducking the entire time. When you do that, it takes away the metal slug feel.
The flame shot shouldn't be a one-hit kill either. You should make the grenades more powerful than the flame shot if you're looking for accuracy.
Character select in the next one?