I've been messing around with AI art recently and I'm really impressed by what it can do. Inevitably, I always have difficulty finding the last few pieces of art for any particular set and end up settling for something mediocre (or changing the cards completely). Now that I have full control over the keywords that go into making the art, I feel like I'm commissioning exactly what I want. I've been using mostly Midjourney. Here are some of the best images I've created for the sci-fi themed set I'm working on now, including some of the keywords I used to create them. Sorry for the giant images, but I encourage you to give it a try.
Red-white planeswalker that can terraform:
Red-green alien beast with trample that likes to fight:
Green-black spiny armadillo with deathtouch and defender: