The only problem that I currently see with behests is the party limit. I find myself having trouble joining behests because there are people camping the battle warden at pretty much every major aetheryte i go to. It's frustrating spending in upwards of 10 anima bouncing around to different camps looking for behests that I can join. I think parties should be optimized based on how many applications are put in in the time limit before the behest starts. It's discouraging waiting around nearly two hours to join a behest, only to see the battle warden tell you he was mistaken and they don't need anymore people ;_;

Behest have quite obviously become a popular way to level up, and I think if the player base enjoys it so much then there should be more done to cater to it on a larger scale. Even if I do find some obscure area with a behest that I can join there are more than likely no more than 2 or 3 other people there, and depending on where you are, and what jobs you have in the party, you may or may not succeed; which can be just as discouraging.