the interesting thing with Wes is the 'Batman argument'. For those of you who aren't nerds in the same vein as me. In other comic forums there are always arguments just like this... the who would win between....? Discussions. It can be an interesting debate when you do Thor V. Superman, Captain America V. Wolverine etc. etc. but whenever Batman was entered into the discussion it always boiled down to one point.
Batman, given enough time, knowledge and resources could beat anyone up to and including Superman. However if he were just thrown into a ring with no forewarning he'd be squished.
Wesley is the 'Batman' of the Buffyverse. Give him enough time and he'll figure out a way to beat Gunn, Spike, Angel, Buffy, Dark Willow, Glory, whoever ya want. If you just throw him into a pit with sharpened sticks with any of those people however and he's a human cantaloupe.