I've implemented some of those suggestions on https://jynus.itch.io/move-the-tower-11 (out of the competition). Now certain enemies shoot back! Let me know if that is a step in the right direction. Thanks for playing my game!
> I thought the laser would autofire too
It does- if it didn't then you suffered a bug or something else strange. Check the updated version above!
> I also just hold back whatever enemies are there
That is actually a valid strategy! To "punish" the player, I have implemented "melee" damage per second if too close.