Bringing the Magic of Magic to D&D: Planeswalkers

I have a plan to introduce a great menace to the campaign I'm hosting.  The dragon beyond ancient, Nicol Bolas.  But I knew I would need an NPC sheet in the off chance that my players decide to do something foolish and fight him.  But Bolas will need opposition, the planeswalkers of the gatewatch.  So I decided I would make a few more planeswalker NPCs.

I'd love to get some opinion on how I've translated Planeswalkers to Dungeons and Dragons.

*EDIT (I've gotten some feedback for the original build and made updates.  More to come hopefully!)

Here's the master post with more planeswalkers included!