Haven't flown the 737, but spent some time in the sim of both the -200 and -800 series. I am current on the A320.
No aircraft would fit perfectly every pilot, but from my point of view cockpit layout is much better organized on the 320. Information systems a relatively clear, push-button philosophy is simple with dark cockpit concept.
Yet the A320 suffers from cluttering of the ECAM when multiple failures occur, and thourough/ continuous study and review is necessary to feel really comfortable.
I have found (in the sim though) the half-lit cockpit of the 737 to be non-intuitive and switches and knobs position do not seems to follow any logic or ergonomic philosophy. In my opinion, even the -800 737 cockpit looks like a dinosaur.
On the other hand, comparing apples and oranges is always a tricky task.
I remember a comment I read years ago about the 737 NG: "I you take a Ford Cortina (1960's) and fit a Mondeo's dash board...well, it's still a ford Cortina!"
