Just got engineering on my new lvl 100, and have been able to level it up almost all the way with only WoD ores from the garrison mine. However, the few money makers that engineering has, the mounts (that don't require engineering to use), all require old world mats. Which are pretty damn expensive on the AH these days.
Also, I don't know the changes to mining in Legion, but I'm assuming without a mine, we're going back to the old fashioned way of only miners being able to collect ore.
It would be nice to have two crafting professions such as engineering and blacksmithing, but it's pointless if I have to buy all the mats in Legion.
So is mining worth it to level up in anticipation of Legion?