Hey, Thank you very much for the great feedback!
For the first point I was thinking of adding that, but I thought if I did that player would be spamming & shoot nonstop.
Kill multiplier, I 100% agree, I just noticed how dumb it is XD.
I am not developing this game any further, because my goal is to release 1 game every month for the rest of the year.
(feel free to follow me on itch & would love to hear your feedback on my next project)