Look, you are talking about this game, which you clearly don't know how to play.
First of all, you ain't beating anyone with inept gameshape players. Think of it like this: your players get tired if they play too much minutes over the week. They need 48-66 minutes. That means roughly, you can play them two games as starters, or one game starter, two games backup. For trainees one game 48 min, second game backup.
Managing minutes is actually one of the fun parts of this game. After each training update at Friday, I take a look at my three upcoming games, and set lineups so my players play reasonable minutes. I scout my opponents, and decide which players will play in which match. For stronger opponent, I put my best lineup, for weaker opponents, I put weaker lineups.
It's fun, and resembles real life basketball coach decisions.
After that basic concept, you'll need to figure out how the economy works. You'll need to build a financially strong team, which will enable you to bring better players, which will bring you more money, then more better players and so on.
GDP? It's the least of your worries currently. Yes, it's probably not the most ideal solution, but it's good enough. Let's say they managed to fix zones somehow, and that GDP wasn't implemented. If you don't have a versatile team, and you keep playing let's say motion and RnG, your opponents will play 3-2 zone. The effect is same as with the GDP.
Anyway, my point is, when you learn to play this game, GDP won't pose you much of a problem.