Todd, you are right, I didn't have a strong support cast the last few years!
Alston, we start 5 OF and have a DH spot (Utility player but DH can only be slotted here).
We have a Minors player slot as 8th keeper. I've been hanging on to Wieters for 2 years now. He never impacted my 7 "real" keepers list before this year as he hadn't played a single MLB game before last May so it wasn't that much of a risk. But seeing my keepers list is still pretty strong, I'm having a hard time dropping one of Werth or Pedroia for him...
In theory a minors spot is one where groom a keeper. Not saying definitely keep him to justify holding him though.
My sense is that had the winning and losing been in reverse, you would be more comfortable keeping Wieters. That is, if you were coming off a 2-year winning streak, your confidence in your drafting ability would be higher.
You didn't forget how to draft the past 2 seasons, stuff happens.
Something else to consider is with Jennings, Crawford becomes a great trade chip and you can already afford to deal Teixeira.
If trading is active, you may want to try to turn Teixeira into a 3B or SS, then in a couple of years, get the other position for Crawford.