If you're worried about racials, let me break it down for you:
Dwarfs get on-demand extra armor when they need it, but it's on CD.
Night Elves get 1% extra dodge, great for tanking.
In patch 2.3, humans will get 1% crit on swords and maces, so if you plan on using those you will fare pretty well as a human, especially in PvP.
Draenei get a free heal and give 1% hit to melee classes, however the heal isn't all that much (my warrior at level 39 has 2500 health, and his heal is 620 HoT every 3 minutes).
Gnomes have escape artist to break (some/all, idk I dont have a gnome) CC.
If you do want to do a warrior/warrior combination, one of you will be DPSing and the other tanking while you level. The problem is, you'll both be fighting over gear for the most part (since until OL most tank gear is DPS gear as well), and you have no healer.
With a rogue, chances are you'll have less gear issues (maybe weapons and capes, but not armor as well), and you'll synergy a bit in that he'll get some nice AP from you, and he'll be able to sap a guy for you. He can probably off-tank one add in world PvE pretty easily...
But, I WOULD recommend a healer. Want a lot of fun? Get an enhancement shaman or a feral druid or a paladin. As a druid, he'd get cat form which is a lot like a rogue in some respects (stealth, melee, energy, openers and combo points, etc), and he can off-tank if you need one. Then when fights are over, he pops out and pops some heals, and you're good to go. Oh yeah, and LotP is +5% crit.
With an enhancement shaman you got WF Totem and he can heal if you need it. If you get a ret pally, you can possibly end up with imp BoM and battle shout up on both of you, for a tremendous ammount of damage. And if you go 2H slam and he goes SoC and both have slow weapons, you can pump out an insane amount of damage.
If you want to do 3 at the same time, I would seriously recommend taking a warrior and 2 of paladin/shaman/druid (probably pally and shammy since you get some insane buffs) and just watch the procs do the damage for you.