I agree you go for the best you can get. I also think that if you get a good prospect, you try to improve the mentor of that young prospect. I'd much rather have a guy like Rivers mentoring someone like Herbert, Love, or Eason, than JB and/or Hoyer.
I wouldn't see it as determining it. At 13, it's not that easy. You might have to take a different path. If you were top 5, you would probably just take Herbert and be done with it. At 13, I don't know. You might go free agent, plus draft pick, depending upon who you like.
We'll know in a few months.
Purely my opinion, but you trade down when either 1) your roster overall is bad and have a ton of areas in need of upgrade, and/or 2) the positions that are in need of upgrade, are very deep in the particular draft.
I think the last couple years we've had "overhaul" needs, and additional medium picks were more important than high picks. IMO, the roster is a lot more balanced/solid in terms of starters and depth.
At some point, you need to use the high picks for the big needs, and for game changing talent. We have a big need at QB, and need a game changing talent at iDL, so IMO, we won't trade back this year. If anything, we could trade up. I'm not really talking about trading our 1st to move up. I'm talking about packaging both our 2s to get back into the top 20 of the 1st.