Guild Wars 2

I want to level my revenant from 1-80 by playing the game. This means no scrolls or tomes.

With pre-purchase would we be able to get the non-specialised version of the revenant to level when it’s ready or would we have to wait until HoT launch?

This would allow me to level them up naturally before they hit the jungle!

No you won’t get the rev early.
Just play him with map complete and then hit the jungle with him.