Games [WIP] Prototype Hunter - looking for some feedback

Hi, some months ago i began to really try developing, after studying about it (and some unfinished projects later) i came with this concept: A 2D top-down spaceship with a melee weapon. It's is not the most creative nor weird game, but i think it would be interesting. I would love some feedback on the idea and the graphics.

Gameplay
It revolves around managing the Heat bar. The Heat bar is an inverted stamina bar which is always draining, when it's empty there's no side effect. Using turbo and attacking will fill it, then when it's filled the ship enters in Overheat, losing health constantly and upgrading the weapons. To exit Overheat, the bar needs to be completely empty.
The game will be divided in missions, each mission you'll need to hunt a Prototype (as the name suggests), hunting it grants a new weapon, some weapons will be hidden in secret missions.

Plot
-Under construction-


Weapons:

Scythe-D3
It's the initial melee weapon, uses primarily slash attacks.

Normal mode: It has a good range and attack speed, with moderate damage and knockback power. Can hit enemies without much aiming.


Overheat mode: Slower attack rate with better damage and knockback power, the third attack (the spin) can get you out of sticky situations.


Rapier-GL
A more advanced melee weapon, it uses thrust attacks.

Normal mode: Fast attack rate and high damage, but a little bit harder to hit. Has a low knockback power, so it can dish a lot of DPS, since it won't move the enemy so much.


Overheat mode: Increasing area of effect on each attack, the third one is a dash that causes damage.



General Civilian Ship Weapon - G11(a.k.a. Civ-G11)
It's the initial secondary weapon.

Normal mode: Triple barrel machine gun, low damage but has high fire rate and each bullet has a very tiny knockback power, that can stagger some enemies.


Overheat mode: Double barrel shotgun, it has slower fire rate and decent range, with high damage, good area of effect and high knoback power...(i'm almost describing a truck).



Some gameplay:

 

The thread was a little bit ugly, so i edited it and added some updates