I like symmetrical controller but I don't think the Dualshock is particulary ergonomic.
Imo the 360 and WiiU pro controllers are the most ergonomic.
The WiiU controller has the best button layout.
The 360 controller has the best triggers.
The Dualshock has the best labeling; geometric symbols are much more immediate and evocative than letters to distiguish front buttons, also R1, R2 for triggers is more immediate than RB, RT or R, ZR.