I considered taking Eldritch Sight here, but at this level, at will Detect Magic just seems like it wouldn't add much to the character no matter how on point it is.

I know I end up taking that spell a lot when it is available to a character in these theoreticals, but seriously, it's amazing and it is so very much on target. Reasoning: These last couple of powers are mostly representative of the Doctor's ability to screw with other people or else his ability to talk for a lengthy period of time and have people just listen to him. Thief of Five Fates was chosen over some of the divination type invocations because it is a way to occasionally inflict bad luck on the bad guys via a Bane spell, which is pretty in character for what we're doing here. The choice between True Seeing and Arcane Gate was also a bit of a struggle but ultimately went for True Seeing. I don't see how traveling with the Doctor would make you pick up shapeshifting, but it was just too on point to pass up. Likewise, Master of Myriad Forms just because. On the 8th level Mystic Arcanum it was a real struggle between Demiplane and Glibness, but the idea of having your own private pocket dimension won out as more decidedly Whovian. They could call up other people about, like their Patron and such, and shoot the breeze. Legend Lore is definitely about knowing lots of stuff and Contact Other Plane feels like an ability someone who travels about a bit would have. Banishment is a lot about dealing with odd beasties. Reasoning: I wanted to get Intelligence saving throws proficient before taking Contact Other Plane, this also let me get Intelligence up to 16.

Truly light elven armor