Issues with storage in dom0

Hello devs, I think you should improve storage management in dom0, because when I (or any other QubesOS user) have little free space we have a problems.
In my use case, I always have no more than 20% free of 200 GB main storage space in dom0.
I have some big StandaloneVMs which have 40 GB for system partition. But why allocated space is not shrink when it is not used? How only 20GB in Gentoo template used, but 40 GB is allocated.

Some time ago storage management mechanism was changed, and now when free space is small, some operations in dom0 is not work.
This changed may be added to prevent 100% fill dom0 storage, OK, but is this case I cannot make backup to temporary free dom0 space, because it is doesn’t work.

I cannot free up space because it doesn’t work.
Very long time I have warning message in system tray,


When I tried to make backups I have more free space, but now I fill it when try to copy files from one Windows VM to other Windows VM to delete one (I cannot make backup).

I restart the host system, and after that I have 7 GB free space in dom0, but I still cannot make backup because Qubes Backup tool crashes.

Now, I will copy required files from Windows VM to usb flash and delete this VM. And I can continue working (and make backup, I hope).

This problems may be with bigger dom0 storage too, so devs should do something with it, I think.

P.S. Thank you for you work, devs, you made the best desktop operating system in the world.