Congrats and welcome!

1) I have found that always taking a wide path (like turning a vehicle with a trailer) helps a lot with your alts, and try jumping when one hangs up a bit. You'd be surprised at how that can affect their path.

2) As for the quests, and general multiboxing, the addon Jamba addon is spectacular. I highly recommend it, and as you seem to be able (and willing!) to read and understand the faqs/directions here, going to the sticky on it [Addon] Jamba - An assistant for multiboxers. 10th Update - 0.4b released. and a little reading will make your boxing much faster and easier.

3) Hrmm, I wish my ignore list was longer TBH. I have quit sending people to this site until after i tell them you need 5 accounts and they respond intelligently. (Yes, I am aware that you don't need 5, but in for a penny, in for a pound right?)

4) Oh, yes they do! It gives you a lot of room to play with odd ball talent specs and class combos.

Have fun!