I'd roll the dice with Bray & I wouldn't take a QB this year. Next years draft class is said to superior at the QB class & with the compensatory picks that they'll have, that will be a better time to pull the trigger on drafting a QB.
As for Smith, it's hard to envision the Chiefs giving up a pair of 2nd round picks for a loaner QB. But if a deal can't get done and Smith does walk, then that's exactly what you have.
And make sure to have a good O-Line built in front of the QB regardless of whether Smith stays or goes.