My shammies melee quite a bit. I have my alts follow me, I use /startattack on them as part of the pull. I have the 4 alts pull together, so the mob walks right up to them, and then I have all 5 chars attack. The mob is within melee range of everyone. So maybe just have one of the alts pull, so the mobs go near him and then it will be by your main by default. On my mixed group (warrior, warlock, hunter, priest), I either charge with my warrior or use his throw. Both work, depending on trying to get mobs to me (with a pally main, shammy main, rogue main, etc) or whether I want the mobs away from everyone. Hope that helps. Good luck.