100% of the WoW players ask this question, what faction to play, horde or alliance? But I think of it in terms as you can play as horde if you like being the baddest or you can play alliance if you want to be more protective, I see the alliance guys more as normal defenders than just brute force like the horde is. I can see now that the alliance faction is more defensive than the horde, and the horde may seem more aggressive overall in quests or battlegrounds. I think it’s the appearance that counts when choosing a faction if it matters the fact that you like how they look. Each race has it’s own special perks and it’s special in a unique way, most of my characters are made based on looks with each race but when I try to focus on the performance I look at the Racial special abilities that they have.
I can’t compare all the races now it just matters which racial passive works with your chosen class that you have. For example, as rogues on the alliance, I think that night elves and humans do better than the rest, just the way I think that undead works better for priests and warlocks at the horde.
So when you’re choosing either to play alliance or horde just focus on things like looks but also racial passives and you can take into consideration even the battlegroup for the PvP and PvE.
You can find a link here for the battlegroups to find which realms work together for dungeon finder or raid finder or random battlegrounds.
And it’s simply your choice to decide either on which realm you wanna play horde or alliance it does not matter. I found out that the horde can be better in PvP than alliance in some battlegroups so if you know one faction is better than the other chose the best.