Keep developing your better strokes, but work on your weaknesses as well.
it doesn't matter how pretty or strong your strokes are when you get a perfectly set up ball with pace*; unless you can hit-back the loopy pace-less backspin shots that your 3.0 comrades deliver to you consistently you will have no hope against the low biting slice or the high kicking topspin that you will see at the higher levels.
* it always feels good to hit a proper stroke off of a decently paced ball; but in tennis you have to be able to adjust to other shots.
Disclaimer: I'm NOT a coach...
Real tennis: https://www.youtube.com/watch?v=yDqnkLJ9BtM