3D backgrounds in 2D shooter, good mix?

Hi, I was thinking for this shooter it might be rather nice to have a 3D background, but more of a token repeating gesture, say for example a repeating city scape which I hoped wouldn't be so taxing plus saves time, also simple geometric sci-fi backgrounds etc, but I wondered also about level end bosses, in a 2D game I suppose having a 3D boss wouldn't be such a bother? and I assume for a 3D background I could construct a few repeating tiles and then once scrolled then offset them to the start and bingo, something like that, anyway it's exciting, cheers

 

You need more enemies, looks too easy with so many bullets ;D

You could do 3d background, sure, many 2d-ish shooters have them, just make sure it doesn't overpower the simplicity of the game sprites or become distracting, and make sure it also doesn't make it hard to see the objects that you need to be aware of. It's tempting to throw colorful interesting 3d stuff in the back, but not if it hinders the basic usability and clarity of what you're meant to be focussing on.