re: Working with imperfect lumber - What are the steps you take to straighten it out?

I agree with HorizontalMike – bowed and cupped boards can be cleaned-up; straightening twisted boards will quickly chew-up both time and lumber.

Also, be very careful with your ‘Plan A’ to flatten the boards – running cupped/crowned boards through a TS is dangerous, as no flat edge is securely supported by the fence – the straight-line jig is good for edges, but not the face. It will be very easy for the board to shift while going through the blade; and there is no up-side to all of the things which can go wrong.

Alternatives…

1. is the hand-plane recommendation, to both smooth the crowns and knock-down the lumberyard machining marks – with sufficient effort and success, you may have a board suitable for you TS approach.
2. is a router jig which will face-plane the boards – YouTube has several good examples: Marc Spagnuolo (The Wood Whisperer) shows this process, in-detail.
3. - Clean the edge, with the straight-line; then, run through a bandsaw (in-effect, re-sawing the board, taking only a small amount of the face).
   Just me initial thoughts.
   MJCD