The philosophy that you detailed is specifically what Bisciotti and Ozzie are trying to avoid. They discussed this during the state of the Ravens presser. They want to avoid the resulting cap and roster situations you have when you follow the idea of windows opening and closing. We tried this in 2001 after the Super Bowl and that resulted in the cap and roster purge the following year. If the Ravens can stay solid drafting and developing coupled with self evaluation of their own roster they should be able to know when they can let someone leave and when they can't. I think for the longevity of the team and staying competitive you have to draft, develop then fill roster holes with good free agent signings.
I think this follows the idea you have with Rice. Committing too much money to positions where you can get solid production cheaper. Can we have that much money tied up into 2 guards when you still need a center and potentially a tackle?
With Rices contact he is 25 and is used a lot. I think you go 5 years and try to do what you did with Suggs. Structure the contact with the money coming up front so you can cut him later on in the deal if production drops. I think the Ravens would help themselves and Rice by getting another back involved more consistently.
I'm not sure right now, but who was the last big time free agent we signed? I can't vision them singing someone to a big time contract to fill a hole.