I caught my Blood Elf up with the rest of my characters yesterday and did my first Wailing Caverns run with all 5 characters. While they were a little high level for the instance I was expecting it to be fairly rough for my first run but it actually went very smooth. I think I died once or twice due to too many adds in a couple pulls but I'm really starting to get the hang of things.
Once the Paladin was in the group with the rest of them I completely redid all of the macros for all of them. I set it up so that the target everyone is following is the focus for everyone and all the macros are based off that. I did it this way so if the Paladin (current leader) ever dies I can just switch focus (with a macro) and everything will continue to run, just short one character. I also cleaned up a lot of my macros and tried to fully utilize the new macro functionality with patch 2.0 to get everything working smoothly with as few buttons as possible.
On a note unrelated to 5-boxing but related to WoW, Paladins are over powered for group tanking. All I have to do is put concentration aura up and have 5 points in the talent that lowers interruption from getting hit. Then I have my warrior tank the primary target with the other four characters beating on it while my paladin just swings and heals. Once the first heal goes off he picks up all aggro except the primary target but because he is in plate with a shield he can tank it all just as good as a warrior. For the rest of the fight the paladin mostly just heals himself while auto-attacking the creep the warrior is on. Meanwhile, the other 4 just peel targets off the paladin one at a time until everything is dead. Using this strategy I have been able to take on a number of double or tripple pulls and chain pulling is easy.
Back to WoW, at level 23 without looting anything but bosses I was able to do WC in 1 hour netting me 10,000xp. At that rate it's under 3 hours per level which isn't too bad at all (just over twice as long as it would take solo questing/grinding). I'll be moving to SFK after one more WC run and hopefully my XP gain will increase noticeably (WC is almost all green to me now).
My quest to level 5 World of Warcraft characters at the same time.