I have 4 accounts, one of which has a 70 tauren shaman, and I would like to try my hand at a 4 elemental arena team with a healer, pretty standard stuff. I plan to primarily arena, and also do dailies, grind up enough faction for enchants, maybe run a few heroics I guess with help. My questions are:

1. As far as leveling, should I roll 4 new shaman, level 3 up to catch up with the current 70, roll 3 shaman and some other 3th class to help with leveling, or boost the 3 new ones with my main shaman?
2. My 70 shaman in an enchanter/herbalist, is there any other professions that would help alot with my new group that I should level along the way?
3. Is there any reason I should roll up 5 accounts instead if my main purpose is pvp/dailies, and I can probably bring friends to a lot of what I do?
4. Any random advice you have.

I'm thinking of going with a Tauren death squad, but if they seem to big I may go with troll or orc instead, they all seem to have advantages. The only bad thing is if I switch from Tauren, I would have to level an extra shaman. Thanks!