I find a multiboxer can be pretty good at any fuction in AV, def, attk, zerg, but some comments.

Tower assault, recapping and defence:
- I have nightmares with my guys breaking follow heading up horde towers, they often end up wandering around in circles on the bottom level while the main caps the flag. Take it slow going up them to make sure all your guys stay together. They are also harder to cap/recap as a boxer, as players can easily move out of LOS of you, just stay in the flag area with your toons back to the walls as much as poss and you can hold off pretty much any assault. Alternatively if none are attacking, you can snipe enemies from the edge to a certain extent. If I have a colleague by the flag (non boxed), I like to put my totem farm just outside the tower and pwn anyone who comes close.
- Ally towers arent as bad in the follow sense, but do take a wide line as you enter and go up the stairs to avoid them getting stuck beind walls. They are also more suited to spreading out and Chain Lightning Pwnage. Intelligent mages however will use the windows in these towers to LoS you.

I found that defending Balinda as alliance can really slow the horde advance. Do it till I die, then res and recap either SH or IWB works well.

If you can get all the way through without being attacked, it is also quite viable to go straight to the enemy base, cap, hold and take the GY all alone. Sometimes you are virtually undisturbed. However, as alliance, it can be hard to make it all the way without getting zerged. I often start the game with this plan in mind, but simply get distracted.

My preferred strat however, is general defence, as ally are generally crap at it, recapping as often as possible. Blocking chokepoints, recapping towers, and trundling back to base to wipe thier attacks on the boss if things are going badly.

Gonna invest the time in getting the Alterac Valley Trinket tonight, as I reckon 4 or 5 chars suddenly appearing shortly after a base cap can seriously dent the opponents progress and turn a match.

All in all I love it. 22k honour yesterday in about 11 hrs play was a record for me.