i think i found some somewhat acceptable workarounds for most level ranges:

-15?-60 afk grind the dragon and orc spot in wetlands with ww monk+ox statue (im not certain when you can start there, i think the area is 15 or 20+, i did it 2 times yet but both with allied races that started at 20). While i did the spot i still had grandfathered RAF bonus active and i went from 20-60 in like 5 hours i would say.

-60-80 i afked the elite mobs in icecrown in the building next to the west of the raid. its slower than wetland but i couldnt stand bc/tfc questing. I think Hellfire Ramparts is a good alternative to boost via instance as you can leave the dungeon upon completion pretty quickly.

-80-90 i boosted lost city of tol'vir which i think is the best instance for the level range. i would guess one run took me 4-5 minutes just killing the bosses leaving the team at the entrance.

-90-98 i afked clefthoofs in nagrand with one team, it works like a charm and you are getting actually quite a bit of fur this way. I somewhat felt bad after i camped the spot and contested it against the oppsing faction with a high level team for 3 days now. With the rest of my characters that still need to hit 98 i moved on to boost in slag mines. You can run slagmines in under 6 minutes and the exp gain is somewhat acceptable. i am getting 600-800k/h i would guess.

Does anybody have expirience with afk grinding mobs via ww monk with ox statue? i dont want to get into any trouble as its kinda abusive in my eyes (but so is the new leveling system if you just want to get it done lol)