I used to spend 8-10 hours per level 70-80. Because you need to do various collection quests to open kill quests, i did the following:
1.Check if its a collection quest
2. Copy the name and check wowhead or thottbot or any database site.
3. Check the follow up's.
4. Are there more kill followup quests? -> Accept and do it
4. Aren't there more kill followup quests, except collection quests? -> Dont accept it and don't do it

This is basically what you do with every collection quest and new zone that you get. I know: Leveling in WotLK is f*cked up. But you have to or you will run out of quests.

And if anyone tells you: Yeah well i cleared first two starter zones and i am level 74-75, thats not going to work with playing multiple characters.

Hope i didn't made you feel bad about playing another 8 levels or so in total agony and pain (because its the truth)

Kind regards and a pat on the back,

Steven from WoWMultiVids