The warcrier overbuffs mixed groups, can not rebuff dead members, and gets their buffs in their 70ies. They lack zerk and empower.
Warcriers have certainly been overboosted, but they are still not the clear 'godly buffer'.
Among the choices the OP presented (prophets or elven buffers including BD and SWS), the Prophet has the most buffs. I maintain that PP and SE are tied for 'most useful buffs'.
I will still always take zerk in C4 - more damage means more levelling speed.
Frankly, I don't see a single member of my clan's groups going unzerked, even with the slight dump to MDef. =) Speed is a boost too! More speed means faster levels also.
Zerk's only going to become more useful. Now you can zerk raid bosses and drop them even faster with nukers. Thanks NCSoft for giving nukers yet another advantage, they really needed it.
At any rate, Zerk's definitely a no-no for PvP meleers with C4. Not that it really matters.
asumming you were planning on going at a mage with 1 person, and a melee at that... if you are with slightly more persons the speed increase will make sure that you reach the mage before he dropped you all, if he hits you for 1K or 1.2 who cares anyway :p