It hasn't always been smart to pick up SG/SF with decent potential. It really just depends on the market and the where the talent levels are at on teams. I started out with a really good SG when I joined BB and managed to snag an excellent PG and a good starting SF along with an outstanding backup PG/SF in my first draft. Best draft I've had to date.
Drafted a solid, potentially better, SG in a recent draft ... 2 seasons ago, I think. At the time, the transfer list was selling SG's and PG's like crazy but the interior post players were going at high costs.
Picked up a few decent servicable big men on the cheap, some expensive thinking they'd be good later on, ditched them later after I finally hit the jackpot ... or what I feel is the jackpot. Got two interior post players at pretty good costs when everyone has been paying attention to the SG/SF positions more. They almost went unnoticed and I landed me my future stars that I've been training.
You've just got to really sit down and evaluate your team, accept your losses for what they are and make a decision based on what you have. I made my decision to keep my good SG and try to build around him. I probably could have sold him and bought a star C or PF for what I made off of him but through time, I've been building a team that I think will be primed to dominate after some serious training.