Love your left sided rock in the first two. The straight up pile of rocks in 1 and 3 looks a bit unnatural to me, but that's just my 2 cents. I like 2 and 4 the best. Also keep in mind fish like lots of spots to dart in and out of, and you'll need places to put corals.
But the main thing is: you like it! Also, it's good if it's not so close to the glass that you can't get in there to scrape algae, and it should not fall over.