If I may offer a very atypical alternative:
Elan Psion. Take the Psicrystal. Manifest "Share Pain" on it and share "Vigor" with it if the fight actually looks hard.
18 Int, 18 Con, 16 dex, 4 Str...12 wis, 9 Cha(modified for race)
"Entagling Ectoplasm" as a cheap debuff. Ego Whip against non-sentient, non-mindless foes.
Probably Telepath for "Psionic Sugestion": target me, which is not only not against their nature but is a very reasonable suggestion so they should get a penalty. And later, "Hostile Empathic Transfer" which gives you a very real benefit to being in melee and allows you to send back all the pain they gave you.
Take the Improved Elan Resilience(CPsi) feat to as an immediate action spend power points to prevent damage at a rate of 4 damage/PP spent(instead of 2/PP as the racial ability).
Also Psionic Body and have almost exclusively psionic feats.
Actually, I played a warforged psion starting at low levels with the Adamantine Body feat, and he could have easily been the "tank" for the party, as he had the best AC and hit points (after using Vigor and/or Share Pain). That's an interesting idea. I also used to coat myself, my psicrystal, and my weapons in contact poison all the time via Psionic Minor Creation. Overall, it was a fun and strong character. You can read more about it
here if you're interested.