Un très court paragraphe pour vous dire de ne pas perdre de temps avec les élites rares. Ceux-ci peuvent bien évidemment éveiller votre curiosité et droppent peut être des objets intéressants, mais l'heure n'est pas à l'affabulation pour le moment, mais à l'optimisation, et les élites rares ne donnent pas assez d'XP pour daigner que l'on s'arrête pour eux !
I do not recommend going for TBC, although I remember Hellfire peninsula to be decent, everything else is rather slow. Instead go for WotLK, Borean Thundra gets you levelled very fast, and then you can head straight for Icecrown at 67, which is also insanely fast, although admittedly has a few elite quests. You can go to Sholazar Basin alternatively. 2 zones should get you 60-80 no problem.
Congratulations on reaching Level 120! There are a myriad of new things to do. The first thing you should do is head to your faction hub ship where you have been doing your mission table quests and footholds to pick up and complete the quests necessary to unlock World Quests. World Quests will provide you an opportunity to grind reputation levels, acquire gear, and gather Azerite. There are tons of new things to do that we will cover in our Level 120 Battle Guide found here: Level 120 Battle Guide