Reggie Wayne and CJ are the two biggest underachievers respectively at their position. Trading away Fitzgerald, who has been productive, and Beanie Wells who has had a solid year doesn't make sense to upgrade 1 position. You are downgrading at 2 positions and upgrading at one position. I understand that you think you need a QB, but with only 1 loss on the season, it seems like you're getting by just fine.
I would still advise you to pursue Sanchez, even though he isn't a big name. He has put up decent numbers this year, he will come cheap, and has a very easy schedule.
Got your message....that's tough. You're 7-1 so you don't desperately need to make any changes. You're essentially trading fitzgerald for big ben, which I wouldn't do if I were you. The other trade you suggested is putting a lot of faith in Chris Johnson...beanie wells have been very good this year, so I don't think I would do that.
I honestly believe it's in your best interest to stay put with what you have. If you're looking to make a deal for a QB, you should inquire with whoever has Mark Sanchez. He's currently a fringe top 10 QB and has over 17 points in every week but 1 this season. He also has a very favorable schedule going forward as he faces 5 teams down the stretch in the bottom 10 vs. opposing fantasy QB.
He's going to be much cheaper than Big Ben so you can keep your starting lineup intact. From there, you can play matchups with Sanchez and Freeman. Tebow and a felix jones might be enough to pull that trade off.