I bought Bit Blaster XL on Steam recently. It had great reviews and was make by a guy not unlike myself (someone learning to make games in his spare time).
The game is simple but fun (very much in the spirit of the old arcade classics). The controls are simple. It even fires for you unless you change the settings to manual (which I did).
There is a good variety of enemies, and you can upgrade your ship as you collect coins. From a physiology stand-point, upgrading to new ships kept me playing longer.
The game is currently $0.50 (50% off as of June 29th). If you have a steam account and like classic arcade games, go give it a try!
Buy on Steam
I found this very encouraging because it’s a simple arcade game like I’m working on.
It was created by a game by a guy that’s “learning to make games in his spare time”. Sounds familiar.