Right-click on the game capture source, go to Transform and then Fit to screen or just Ctrl+F.
There's really nothing wrong with your stream, no dropped frames or frames missed from encoder overload or rendering lag.
If you do start having issues, start with turning off HAGS and be aware that in many cases, wireless connections can cause issues because of their unstable nature. Streaming really requires a stable connection. Often wireless connections are fine, but if you have problems, the first troubleshooting step would be to switch to wired. We highly recommend streaming on wired connections.