Run an outside based offense based on your star...most likely motion...but...
I would consider getting rid of Merlin South and getting a more balanced squad. You might want to keep him until you are out of the Cup.
Your arena needs the most attention. You just won your league so your pricing should go way up. Like 16 bleach, 52 lower, 175 court, 1200 box. Then you should add a lot more seats depending on what is selling out. Then just keep building your arena.
You may want to scrap this whole season and train your Hall of Famer and your Superstar at a guard position to get your HOF some outside skills. Pressure would probably be best, but try to mix in some one on one forwards or guards.
Then just buy 2-3 15,000-20,000 salary players to keep your team from being dropped back down to Div 5. A good time for this would be around all-star break. Consider guys near age 32-35 so you don't overspend on players. By the end of the season you may have a chance to make the playoffs. But your biggest concern needs to be your arena.