You can try to avoid the collections, but most of the Northrend chains alternate kills - collections.
Sometimes you get 2-3 kills before a collection, but then you can get a 2-3 collections before the next kill stage.

If you can look at the collection stage as a mini-grind, mindlessly killing mobs - with the bonus of a quest reward over and beyond the grind, that can help with the collections. I was so sick of collections, for a week or so I basically did mindless grinding on a team, while having 95% of my attention on my dvd player and went through most of a season of CSI. Collection quests is essentially the same thing, except there's a reward at the end, plus they can open the kill quests too.

If you don't want to do collections at all, you'll quickly run out of quests to do.
As an alternative to collection quests, you can move to another zone and do the kills you can find there.
But you'll reach the same point in a bit.

Instances are the equivalent of the grind, except there's a pattern of where to go next.
You'll generally gear stronger in instances, but wipe a lot more too.
Quests will make you a lot more gold, unless you have an enchanter to DE all the crap you get.

You can also level fairly well in PvP battlegrounds.
It's not as fast as it was, but its still decent.

Mix it up a bit, don't get burnt out; take breaks when you need to.
It helps to always have rested, but not sure that you have enough toons/teams to alternate.