I'm coming back to the game after a few years awwy and had similar questions. Check out the mentor list and send a few guys a private email with some of your specific gameplan Q's. I've got some useful tips that way from guys who've been playing a long time and had success.
I'm in a conference with 8 teams currently projected as a lock in the NT and 3 more bubbles, so every game is like a NT game. I've found gameplanning to be huge. A few things I'm trying:
Lineup: I'm changing up my depth chart to match strong defenders where they need to be, best rebounder, etc.
Opponent Defense: If I see a crazy wicked good defender, I adjust distribution down on my player facing him. If I see weakness in defense, distribution goes up. For zone defense, I look at whether they defend inside or outside better, then adjust distro.
Run slowdown if you need luck to win. I was predicted to lose a game by 20 points to a projected 1 seed. I ran slowdown and won the game. If you think you're outmatched, slowdown.
Definitely send a private email to a few mentors. You'll get suggestions for different tips, and can go with what makes the most sense to you.