Hi, I'm new to freelancing, but I have 19 years of experience in IT and software development, including in Python.
What you're asking for seems relatively straightforward:
1. Remove 3 features from the GUI (eg. "Add Feed..." function).
2. Add & Delete Feeds from the command line.
3. Turn off logging (or redirect log file, if preferable).
All of what you're asking is doable but there will be 2 issues you'll need to understand/address in order to successfully implement what you're asking for:
1. If you remove the "Disable Updates" function, the app will check '[login to view URL]' for updates and when an update becomes available, it will update itself and overwrite the changes that have been made to the app (i.e. the changes you want). You'll either need to redirect the update functionality to point to a different URL (unless you "own" [login to view URL] and can control the update process on the server), or disable updates completely.
2. You'll need to run multiple different instances of the [login to view URL] app - the first instance started without command line parameters, will run the GUI app. Subsequent instances which include your specified command line parameters will run to add/delete feeds to/from the feed data file. Some form of refresh mechanism to check for changes to the feed data file will need to be implemented to run periodically in the GUI instance.
If you'd like to discuss further, I'd be happy to do so. Looking forward to providing you my services.
Regards,
Gavin