Many players these days hit the ball hard. This has produced a large number of players who actually prefer to play against the hard hitters.
If it seems like the better you hit your shot and the faster you hit the ball, the better your opponent responds, it may be time to change things up. There are several ways to do this.
First, try hitting higher balls with more topspin deep and down the middle of the court. You may be able to push your opponent back and get a ball that you can hit on the rise and attack. Another good idea is to use some slice (backhands) to change the speed and the bounce of the ball. If possible, just mix these shots in with your regular shots so your opponent is not able to adjust as quickly. You can still hit some balls with pace and they will likely be more effective since you have shown the ability to change up the point.
It also may make sense to play some points moving forward since it will be more difficult for your opponent to pass or use your pace successfully. Don't panic when you see your hard, well hit shot come back even faster.
Use one of the ideas above and you will likely see more unforced errors from your opponent and less certainty on their part about how to win the point.