Nice serves. I think your problem is that you're too accustomed to either making an error, either to your opponent missing the return/the ball not coming back. So as I said earlier, you should work drills on point construction around your serve, how to prepare for the returners' return, and maybe take a bit some speed of your serve and add more spin to make it harder to return. And as other here said, it would be interesting to know your 1st serve percentage and the zones you hit at serve. Both are important, but at least the 1st serve percentage would be useful to us.
For example you could try the 1-2 punch strategy in which you assume the ball will come back anyway. That's using your serve as a setup tool. You also have serve and volley for example if you know how to approach the net. The videos are in order, so it's preferable to watch them in order.