racial traits can hinder also. - depending on class and profession.
hunters and mining/herbalism do not compute.
dwarf and mining/herbalism/hunter do not copmute.
gnome and engineering.
getting professions and class is more impostant.
hunter/druid/rogue with leatherworking. (can use leather)
Mage and tayloring (can make better armor then most of what you pickup. I could make blue items at lvl 29
mage and alchemy - they can't heal themselves.
warrior and blacksmithing.
I went undead warrior and must say i see some great bonuses for doing so. The three i use most are WOTF , Canabalize and Under water breathing. I came into this class from a Night elf hunter and I love the extra defense the hunter lacked. I loved so much i am going full Protection/ fury as my spec. In PvP it usually takes 3-4 to bring my 26 undead warrior down and in PVE grps love me cause i can hold agro so nukers nuke. Over all I thought of going Tauren or orc as a warrior but think undead makes a better denfensive warrior due to WOTF and Cannabalize.
I have a 60 Human Warrior 31/20/0 (Mining/Blacksmith-Swordsmith) with an Arcanite Reaper. I have a belt that gives me +40 attack power bonus. With my Battle Shout I get about 1k melee power. With BOM from a pally i get over 1200. Using Mortal Strike rank 4, I crit like a mad man and target priests off the bat.
I havent played much as horde, so I cant say for them.
I'm partial to warlocks because they just feel more interesting to play. Granted, PvP is really, really hard to get used to. I have mage and warrior alts, but they seem to get rather boring from time to time.
I've only played alliance, so I can't say for horde...I have a 60 warlock, 60 druid, 60 priest and have played all the other classes a fair amount... I would say that either of those three are my favorite. For leveling, the druid pwns all (in my experience...i.e. don't start a flame war) if you know what you're doing. The druid is an amazingly versatile class that, when well equipped can play the role of tank, dps, or healer. As a previous poster mentioned, if you choose a druid, your race has already been chosen.
The warlock is my personal favorite because it's complicated class to play with many options and if you're well equipped and well experienced, there's no one who can beat you in PvP. 6000HP and Soul Link with a felhunter out = pwnage of *anyone* who's stupid enough to engage me. It's that simple. I chose a human for the simple reason that I'm not a fan of gnomes.
The priest can be a formidable class as well...and if you're interested in that, I would opt for a Nightelf...shadowform comes in handy, at least for me. With the last patch (1.10), the priest talents got a decent overhaul that makes spec'ing as something other than shadow, a viable option. I prefer a heavy discipline build with holy towards the end. Shadow never impressed me despite its obvious strongpoints...probably 'cause I was the warlock first and wanted to move away from shadow?
I play a 60 NE warrior and a 40 human Rogue, also a human warlock at 18, but not very much (I really don't like all that casting).
I think that the bonuses available from kit and buffs far outweigh the racial abilities once you get to 50-55, and I have complementary professions on my alts so that they support each other with potions and enchants.
My warrior is fully prot specc'ed, and the extra health or stoneform would make almost no difference at all when facing ZG bosses or raiding in MC.