You have put a massive amount of work into this idea so I applaud that.
I do think that if you decide to rebuild then your fans will punish you. I know certain NBA teams keep their fans constantly fed with the "we are rebuilding" line as they suffer through season after season of bad teams. For some like OKC it is true others it is just a line. I think the thing is to have an exciting team while rebuilding.
If you have drafted a $7,000 18 year old HoF potential who is your starting PG your team fans can get excited (like with Ricky Rubio right now) but too often "rebuilding" Buzzerbeater teams just have random scrubs getting thrashed every week and there is really nothing for the fans to look forward to.
I don't know how the GE can decide who is truly rebuilding a an exciting young team that could get fans through the gate and who is just tanking at the salary floor.