Easy to care for plants, like golden porthos, ZZ plants, etc. Or, even tasteful fake plants for those no light areas like bathrooms without windows.

I second buying thrift store art, keep in mind, you might buy a few that you end up not showing/displaying, ok to redonate.

Also, two huge things to help keep your place neat is to make sure every item has a home, and more cabinet/covered storage is good, for example, buy furniture that has drawers, like beside tables, coffee tables with drawers, couch side tables with drawers, etc.

I have large magnet marker board on my fridge that I use all the time, you could also get a nice wall corkboard, or even paint a wall with "black slate" paint so that you can write on it with chalk. Also good to have a filebox with hanging folders and use it to keep papers organized, and have a system for your mail so it isn't sitting around.