Honestly I'd rather they went with something that captured the epic feel of BC, but without some of the gaudy frills that came with the Illidari. It'd still be way better than time travel ending in "it was all non-canon..."
- - - Updated - - -
As far as classes go, Lore > Abilities.
And warlock lore has moved further away from DH lore.
I understand your hurt that it's Warlords of Draenor, which pretty much murders your Tinker idea on the spot, but I'll let you grieve. We can come back next November and debate it again.