I voted for the first one, because I find it most visually pleasing (I've been thinking about getting one for myself).
However, I would say it depends on your mood/intention.
If you'd like to cover your tummy (like I sometimes do), I also like the third one.
But if you're trying to be really naughty, I'd suggest the last one. You can't get much kinkier than a crotchless teddy!
Hope this helps, and good luck with your choice!