I hate asymmetric sticks, it ruins how I play a TPS.

Symmetrical.

I like to have the left stick in the upper position for 3D games. The position of the other stick doesn't really matter that much to me (in FP-games I prefer it at the upper position and in most other games I'd like to have the face buttons there). So I do like the Xbox Controllers and the WiiU Pro Controller in regards to their stick placement, despite one being asymmetrical and the other being symmetrical.
If we ignore the Wii U Pro Controller and focus on the Playstation and Xbox controllers, I'd prefer the asymmetrical layout of the Xbox controllers.

I like Pro Controller and Dualshock 4 style, because it seriously helps in racing games.

Symmetrical, but only in the Wii U Pro controller's case. Never cared for the DualShock layout.

The asymmetrical sticks of the Xbox 360 are a close 2nd though.

Asymmetric. Sometimes, when I'm playing a minigame the symmetric layout makes me do the same thing (or mirror image thing) on both sticks when I really need to be doing two separate things. The decrypter gadget in the Batman games is a good example.

I love how in most cases I can tell what the answer is gonna be just by looking at a person's avatar

Symmetrical. Just seems and feels right for me. Never had any problem with it.