1. Draft a potentially generational talent, hope he pans out, and surround him with average players. We've seen this movie before.
The only other time the Bears used the #1 pick was in 1947, so you may have seen this movie before, but most of us haven't. Who have the Bears missed on that was touted as a generational talent? Trubisky was taken at #2 and the Bears were criticized for that move from the word go, so it's not like he was labeled as "can't miss" and was a bust.
2, Keep a serviceable, locker room leader Fields. Find out what his ceiling really is by surrounding him with better players. Trade down (maybe twice) and load up on good 2024, '25 and '26 picks PLUS an immediate veteran starter like the Bears got last year with Moore. Talk about an impact player! Using the draft, trades, and free agency, give Fields an above average OL (for once) and a strong #2 WR to complement Moore.
Fields appears to be well liked, but I really haven't heard anyone say anything about his leadership qualities. You failed to mention that if you keep Fields you have to pay him. Extending Fields will cost around $50 million per year. Not saying he's worth that much, that's just the going rate for starting QB's. That's going to limit what they can do in free agency. Also, you're assuming they would also get a veteran player in any trade back. Just because the Panthers offered that doesn't mean another team will do the same this year. Who would you want from the Pats or Falcons (two top 10 teams who will likely be looking for a QB)?
You also assuming a #2 WR would be available wherever they end up trading back to. You didn't even mention where you would have the Bears drafting or trading with, just a lot of assumptions.
As has also been mentioned, there would be a return of picks if they trade Fields and would have more money for free agents with a QB on a rookie deal.
There's also the fact that some of these teams that may be interested in trading up for a QB may go after someone in free agency. The top QB's are likely to be Cousins, Wilson, Mayfield, and Flacco. It's a fair bet that at least one team who needs a QB and may have been willing to trade up will get their QB in free agency and keep their draft picks.
As of now I'm still on the side that thinks they should keep Fields, mainly because I'm not sold on Williams, draft Harrison #1 and at #9 take Turner. That gives them the best WR and Edge in the draft. Use the 3rd round pick on a Center and look for an interior DL, Safety, and OL depth in free agency. If the Bears keep the #1 pick they will need to address most needs in free agency as they currently only have 6 draft picks.