Nice old school PlayStation vibes here!
Few comments:
- All of the assets are quite detailed, while the character and enemies are not. This inconsistency is constantly recognizable and make you feel not well. Consider sticking to the low poly simple texture or the high high poly detailed textured. Consistency is way more important than how the individual assets look. The quick solution is to get back to the blender, ad subdivision modifiers to character and enemies models and export them back to the engine.
- There is no shot impact effect at all, so it is super hard to get if you missed or not. Consider adding at least sound effect for the enemies when they get damage, should be easy as you already handle hits.