After trying out the different options, I have ended up using my Xbox controller. Still, I'm not entirely sure this is the best choice. I always had a bit of trouble aiming with thumb sticks.

So, what are you using?

Such a question is so subjective (personnal preferences, sensibilities, situation zt home to play, eyc) that you can't have a rel answer until you try by yourself for several hours each options you have.

For me, top down shooters "Asteroid-like" were, years ago, with keaboard+mouse, and for some years, twin sticks controller for simple ones like Nex Machina, I'm less precise with that but I can play from my couch.
For samey gameplay, I can't see myself playing SPAZ with controller, it's almost impossible to me. (because of shortcuts)
But I also play games like Ion Assault with Keyb+Mouse. And others like Waves or Geometry wars with controller.

Very situationnal. And a bit part of personnal feeling. (I played combat games such as Street Fighter, Mortal Kombat, Rage or One Must Fall 2097 with keyboard for years, and I have a friend of mine who play Super Meat Boy on keyboard, even if he got the same arcade pad as mine)