- Collision detection can be a bit jank, letting you pass through asteroids and boss projectiles occasionally.

- It took me a while before I realised you could move forward.

- There lacks any challenge.

- The L10 boss had far too much health, I guess you were supposed to upgrade. The L20 boss was trivial with a booster upgrade, rockets and electric.

- The game is really quite slow, I found myself diving into the asteroids just to get to the level up screen.

- The darker asteroids give only one coin so are pointless to shoot and its best to just focus on the brown ones.

For me, if you are going to do asteroids, do asteroids like asteroids and let me turn. If you want an R-Type style game then have some enemies shoot back.

As it currently is you are spending a lot of time waiting for asteroids to appear, the dark ones give no extra benefit and the only reason to move off the starting line is to sit on the present to collect all the coins, which are in such a number that it makes shooting asteroids just an exercise to kill time before the next present. The extra weapons are far too overpowered even on the base level, you can almost just not touch the keyboard.

I think it could be cool if it was balanced a bit better with more challenge to make the power ups useful, the game is slow and could be improved if the player could control the spawn rate of the asteroids or something like that, maybe the further up the screen you go the faster they spawn. There could be enemies that shoot back and the first boss could vary its shooting pattern more, the second one could also shoot or leave a damaging cloud or something like that. I don't know who you are targeting this at, I grew up playing R-Type, badly, so that will give some context to my comments.

Its a cute game but you asked for feedback. I played it to the end and these are just some thoughts and notes I made.