Offensive flow is passing, alloy-oops and turnovers basically. It helps, I have never won a game based on that but I have stayed in a game with it.
I would generally base you defense one your opponent's offense. If they are and outside team then full court press and 3-2 work. If they are inside then use 2-3.
On offense, play to your strengths, but don't be predictable. I always want my forwards to have the ball so I use look inside and low post depending if I want to slow the game up ( for a team I am better than and want to blow out) or slow down ( a run n' gun team that i am equal or worse then)
Yes, O-D to Outside Offense and ID to Inside Offense.
One more tip, when preparing to win a game, tell your players to score at least one more point than the other team!