What houses should I get for my HO scale train layout?

How about these?

Setagaya

Check the Walthers catalog. I’m not sure what you have in mind with “laser art.” Structures are normally 3-dimensional and assembled as kits, or (for more money) pre-assembled. For backgrounds & backdrops, where the viewer can’t see the rear, consider cutting a structure right down the middle to make two out of one. In HO scale, using N gauge or smaller structures in backgrounds fits more stuff into the same space & creates so-called forced perspective.

They make model houses in all eras, from Victorian to modern.

Dover has a wonderful series of paper cut-outs for the H.O.