Quoting kryo, reply 10
Having shamans and paladins available to both sides is in the better interest of game balance. It also allows them to be distinct classes with their own flavor since they no longer need to completely counter each other.
It's also really boring.
They made undeads into humanoids because it was to hard to balance. That's the main problem with multiplayer games. It's very hard to balance perfectly and keep things interesting & varied.
They also gave them Will of the Forsaken, which was different (giving them back most of their undead immunities) and ridiculously overpowered for years. So much so that it drastically skewed the races people were playing in high end (competitive) areas of the game. Original Fear Ward had the same problem, once word got out about it people were flat out stupid for playing an Alliance Priest that wasn't a Dwarf (and the ratios on old vs new servers showed that impact as more players realized how strong it was).
In a single player game, that isn't a huge deal. In a multiplayer game, making one set of things flat out better then another set of things will result in most players taking the easy road. People want to win, and when you're competing with other players, why gimp yourself?
I expect Elemental's factions to have varying strengths and weaknesses, and some variety. That's good. But if we ever get to a point where X is flat out worse then Y at everything, that's not balanced, and it's bad.
(WoW is fun to watch for balance because with so many top end competitive guilds and a huge theorycrafting community, every advantage gets found and used to try to get ahead. They're in a pretty good spot now, but nobody was particularly happy with the 3.1 "Bring a Death Knight Tank or don't do hardmodes" mess that Ulduar started out as. It was especially not fun for guilds that simply didn't have a DK tank, they were playing a much harder game then those who did.)
