High King≠Supreme Commander
No. The game explicitly states the humans, dwarves, gnomes, and night elves are under Varian's command. It specifically leaves the draenei out.The Draenei and Worgen in Lion's Landing formed pretty much the bulk of the troops there. They all were in Alliance uniforms, with the Lion tabard and all. They were under Alliance command and at Varian's command.
I agree with you on one point : we don't see enough of Velen and the Draenei.
There are only a couple worgen in the whole place.