Honest thoughts on all the options:
Supershroom - Boring idea that's not creative at all, it would basically be another GEx or even a regular Community Contest.
PixelPest - Really interesting idea. It reminds me of MaGL X2, but instead of names it gives you designs.
MECHDRAGON777 - Cool gimmick, but there need to be enough themes to make it really work.
Dragon Fogel - The rules are pretty unclear here. For example, what would happen if two people picked the same level? I like the idea, though.
rpgfan4 - Could be interesting, but I don't really like it. It's basically the same as the contest DarkMatt had a while back.
sebby19 - So it's basically the same as my music contests :^) I can't say I'm against this idea, I'd even be willing to judge this one if it wins.
Sturg - Similar to PixelPest's idea, but I prefer that one over this...it feels more concrete.
So overall, here was my personal order:
0.

1. PixelPest
2. sebby19
3. Sturg
4. Dragon Fogel
5. MECHDRAGON777
6. rpgfan4
7. Supershroom