Thanks for the feedback about GitHub Desktop @yoricw. 

>I can only add a repository
not add a folder with multiple repositories inside

At this time there is no option to scan a folder to discover all of the repositories available, but this is something we are tracking in https://github.com/desktop/desktop/issues/1574. The best way to add multiple repositories is to select them all in File Explorer and then drag-and-drop them directly into GitHub Desktop.

>I have no way to orginize or SubGroup my repository list
All 30+ repositories are just in 1 AlphaNumeric list
with no Grouping or SubGrouping possibilities

This is something that we discussed in desktop/desktop#6460. At this time we do not have any further plans to make changes to how repositories are organized, but this may be something we revisit again in the future. You can find some further context in that issue.

I hope that is helpful. Please feel free to drop any further feedback you have into the issues I linked – we especially appreciate hearing feedback about how a certain feature would improve your workflow with GitHub Desktop.