For your tank... I'm assuming you meant which race should you be, not which class, since you seem to want to be a warrior! Well, if you were Horde side I'd recommend Tauren for the health buff. But honestly, I *never* pick a race based on the racial features - only based on the flavor. If you are going Alliance side, I am quite partial to dwarf warriors myself but pick whatever seems most fun to you!
Players’ relationships with the NPCs around them have been hit-and-miss over the years. One of the original issues with Thrall, the Horde’s original Warchief, is that players began to refer to him as “green Jesus,” because of how infinitely powerful and infallible he was. But he’s been gone since the Warlord of Draenor expansion, and with the death of Varian Wrynn and Vol’Jin at the start of Legion, the old guard hasn’t been there to guide players the same way as it used to be.