The difference in dps with a full pve set compared to pvp gear is just amazing. BUT, most fights (including trash) is either just a zerg or you can cc everything but 1 or 2-3 mobs and take them down easily. I run heroics with my 4x ele sham team and prot pally fairly easily. Some fights are difficult but you get that.

So yea, if you earn honour really easily, convert to start with, then start farming your VP for awesome pve gear. And run LFR as well, the drops in there will help heaps.