I'm positive you can make out who this is supposed to be. Regrettably, there are no better pants for this cosplay since every other option that isn't a skirt (Ascalonian pants come to mind) is simply ill-fitting and ruins the character's outline (he does not wear tights). Shaders were set to highest and post-processing disabled.
Sadly, the Celebration Hat's been unavailable since the first week following the game's launch and the boots require a few Hall of Monuments Points from Guild Wars 1 to be unlocked.
The raptor skin shown in the first image is the Savannah Monitor and its dyes are (clockwise, starting from the upper left corner) Wasabi, Wasabi, Fog, and Amber.