I'm rather against 7 heroes; you can already steamroll most of the areas with the current 3 hero builds (Rac/Sab/Discordway, ect), so 7 heroes would just be ridiculous. Heroes were really only introduced so players could have better alternatives than henchies when they needed a few more party members and there weren't any human players available to fill the necessary roles. If Anet let us use 7 heroes, a lot of players would never bother grouping up with human players for anything short of elite hardmodes and Urgoz/Deep. Making it so its easier for players to avoid playing with each other is not something an online game needs imo.