You clearly haven't researched at all. Eddie Jackson would add 7.1 million to the cap if you cut him and if you traded him then he would save 2 million. Eddie Goldman would add 5.05 million to cut and about 400k to trade. Those are pretty stupid moves to make.
So yes it really is hard to do what you suggest as what you are suggesting would actually increase our cap not decrease it. If you cut/trade/restructure Fuller, Hicks, Graham, Skrine, Massie and Leno, you still don't have enough money right now to sign ARob, Trubs, JuJu and the 25 other players you need to fill out a roster. But don't take my word for it.
Become the fantasy general manager for the Chicago Bears using the OTC salary cap calculator and roster management system
overthecap.com
Feel free to play with the above which allows you to mock up any combination of moves and let me know how you creating the cap space you need to pull off what you are suggesting.
Just as an example, if you trade, Fuller, Hicks, Goldman, Jackson and cut Graham and Skrine, that only gets you to 28 million in cap space assuming 176 million in cap. You simply cannot sign ARob, Trubs, and Juju plus 23 other players for that amount.
So lets also cut Massie and Leno. That gets you to 45 million. Ok so 4M costs like 24 million on a tag. Let's say ARob 1st year salary is 10 million and Juju's is 8 million. That is 42 million. So you have 3 million left. That is not enough to sign 23 players and now you need a new FS, two new guys on the DL, a new starting CB, new LT, new RT. And you propose to fill all those starting positions and remaining roster spots with 3 million?
The math does not work. We will be lucky if we keep one of 4M and ARob much less trying to keep both plus add Juju.