The Raspberry Pi 7″ touchscreen is a great addition to your Pi. In my case, I use it for Mission Control. The issue I had with the touchscreen was all the cases or desk stands out there limit access to the GPIO and the SD card.
So I did what I do best, I designed a desk stand that allows me to mount the Raspberry Pi to the side of the touchscreen. Pictured is a Raspberry Pi 3 Model A. It works well with the Raspberry Pi 3 or 4 model B.
You may also notice that I upgraded the power wires from the included seven-strand wires to 24 AWG silicone insulated wires. I found that the included wires did not provide enough power to power the display.
Here is the back of the stand
You may download and print your stand from my Thingiverse page: https://www.thingiverse.com/thing:3387445, or from my Printables page: https://www.printables.com/model/332793-raspberry-pi-7-touchscreen-desk-stand