1. I am sure Doc is telling Rondo to play defense. Rondo just isn't, even though we all have seen that he can. Telling him to do something and getting him to do it are two completely different things.
2. Pierce is already playing the least minutes of his career. His minutes are being limited.
3. The Jeff Green you are thinking about is the Jeff Green that got 37 mpg in OKC and put up okay numbers on a bad team. Jeff Green, given his skill level and performance doesn't deserve more minutes. Also, Green is a pretty passive player. He just CAN'T man up. He doesn't have it in him.
4. I agree with starting Sully. I think he has earned that right on this team.
5. Wilcox has been injured. He was backing up KG before the injury. Even though he's back, I am not sure he's completely healthy or physically ready to play. When he is, I think you will see Wilcox getting backup center minutes.
6. While I don't think Bass is garbage, I think he has returned a bit to what he was before having perhaps his best year last year. I do think trading him is going to happen as he is expendable now that Sully is shining.
7. Giving Barbosa backup PG minutes is minor tinkering at its very best. I don't see it making a major impact.
Overall, I don't see the OP's plan working to turn this team around.
I think age has caught up with some of the team's oldest players and its starting to show. I think some players are a bad fit for this team. And I think the thing that will turn this team around more than anything is the attitude of the players themselves. When they decide to put in a consistent 48 minute effort every game, they will start winning like they have in past years when they were putting in that effort(07-08, 08-09 until KG's injury, 09-10 to start the season and in the playoffs, 10-11, 11-12 to end the year)