Currently, if you're a dps you go Worgen/Panda, if you're a Healer you go Human. Thats pretty much the choicesAlliance have for PvE min/maxing (with a few exceptions like Ret Paladins or Shaman healers that don't have their theorical optimal option). Pandas are availlable to both factions so they don't really count in the balance.
While Horde DPS classes have choices between Orc, Troll, Forsaken (new racial) and Goblin. Horde Healers usually go Blood Elf, but Troll or Goblins can also be good in that scenario. Taurens needs a buff too.
Lets give opinions and suggestion on how to Make Alliance PvE racials more attractive, when you see entire guilds (Vodka for example) go Horde purely for racials, there's an obvious imbalance. WoWprogress rankings kinda shows it too.
Humans : They are already overpopulatings and very good in PvP, would be hard to buff them, also best Alliance Healers, maybe turn their spirit racial in Str/Int depending on specs?
Night Elves : Replaces Wisp ghost form (about as worthless as Undead's scuba tube racial) with the old Night Elf Priest Spell, Starshard if i remember? Procs on any attack or healing spell to your current/nearest targets and puts an Arcane dot scaling with AP/SP.
Dwarves : A Strength/Spirit/Int proc instead of their Arch racial?
Worgens : Good as is.
Draenei : The 1% Hit is pretty good tbh, its pretty debatable if a buff for them would be needed, if you have any ideas feel free to toss them out.
Gnomes : Never played one, no idea here. Maybe an engineerish tinker ala goblin? Toss some ideas for them Gnome fans.
Signed, a min-maxing Alliance Hunter tired of race-changing back to Worgen every tiers (and i hate Pandas).