Actually you are now getting to the real painpoint...
Slot 0 is a recovery slot and is also used as a backup mechanism when you insert a USB stick with a specific file on it on the USB. It contains also the directories that contain the other 'slots'. So it needs special handling and when you 'break' it you can lost all the other slots. I did not decide anything, I just mentioned the fact. So that is also why it is not recommendable to flash it online. And yes when it is an option, we are aware of it, but users will make the mistake as they do not know, lost slots or event think they brick their box (unless they can restore it with flashing via USB).
I recommend to put it on hold and sleep on it for a moment as I prefer a 'real' solution. Actually what VIX is trying to do, making it a real kind of recovery 'image' is the best option we have. From the first time the idea came up my feeling was I miss a recovery image, but it may take some time to get it done somehow.
A few line of codes can indeed arrange you can flash slot 0, but the code is full of exceptions we should try to avoid. And when the slot 0 is a real recovery thing instead of a full image with enigma2 functionality is what I think we should prefer. As longer I think about it making slot 0 a kind of normal slot for the user is for me more and more not a good approach. It always somehow 'breaks' the recovery 'mind of thing'.
Just to let you know we have cmd images for all devices on https://images.openvision.dedyn.io for more than 2 years.
No enigma2
No GUI
No python (optional)
Less than half in size
OSCam pre-installed
Network only and command line