The Nautilus is indeed a strange watch. When I first saw it, I didn't like it neither. I said - it has "ears" and I found it very strange. And then I tried it on my wrist and the rest is ancient history, I became a fan. Something about it on the wrist, slim, sporty, still dressy, some polished elements, some brushed, but overall a restrained look, makes it a rather likable watch on the wrist. But now, I don't wear it as it's too recognizable and it's a safety issue in much of the world.
Seems like you've done a lot of due diligence. Good luck with your search and please report back with whatever piece you buy. You can't really go wrong among these three, although the 5015 might be slightly risky.