Bills need their draft picks, and they need them to hit so they can have starters on rookie contracts. Fantasy/reckless to trade away high draft picks for expensive free agents you can't afford. Bills need to draft a rookie OL and learn how to play him. Other teams do.
Bills effectively need at least two interior OL given that Morse is a high concussion risk. Center too important to just have a backup that can only shotgun snap it. They could replace both guards and center in an attempt to improve and get younger and I'd totally be OK with that.
Get better guards and your tackles look better. Give Brown a full summer to heal and recover and I think he's better next year.
Perhaps most importantly, figure out what your offense and blocking scheme are and what players you need to execute them. I don't feel OL coach, OC, and head coach had that together. Do we go 90's dolphins and look for pass blocking only? Do we want at least one side of the line to be capable gap blocking guys who can move DTs when needed? Why was Teller thought so little of and who assessed him as low value?