It's true, your racial stats only matter in the begining of the game, but then again WoW starts at lvl 60... As for making an undead rogue, some people say it is the best for rogue, but those are just opinions. I personaly ( havent made a rogue yet, still picking between warrior or rogue, but have a shaman )am going to make an undead or a troll rogue. Im picking just on the fact of the 2 races are so freakn' cool.
btw, the Horde team is the actual " good " team. People always call the more vicious people bad =( the NE's are good too, but the humans are the most evil in the game. That's if your into the actual Warcraft storyline.