what i did is bought 4 vanilla copies. I linked each copy with a main account and boosted 2 mains and 2 vanillas at a time. I boosted 2 horde characters per account and 2 alliance(dorfs weren't out yet). for a total of 32 characters to 60. I gifted 60 levels to my alliance dorfs and going to gift 60 levels to my goblins. I also boosted paladins on each faction and 1 set of mages and 1 set of druids if i wanted to go that route in the future. It took about a week to get them all to 60.