Yes you can on PC and Xbox 360. As for the problems I'm seeing, it's the same on what you get User vs CPU, which you listed here.
http://www.operationsports.com/Eccen...-cpu-gameplay/
About using the quick game slider set, I think I'll use the changes on offline association except the player speed, game speed, quickness and speed since you can't change player speed on My Career.
Slimm44's latest roster, which I just downloaded, also has coach profiles fastbreak on all the current 30 NBA teams on 0. I don't know if your values would still apply.
I'm not so sure about your injury sliders though.. each season I get atleast 1-3 players in the league get injuries which lasts for a season. I've simmed games to see how the injuries would work out. Is this normal?