Two things I would like to see for the stable release are: 1) Debian develop its own desktop designed for stable, and 2) remove buggy packages from the stable repo. An examination of the stable repos over the past 15 years reveals that Debian has allowed a lot more non-functional software in the stable repo these days than it did 15 years ago, and to the detriment of its users.. I expect software in the stable repo to be fully functional, and if not has a maint ainer who is willing to fix it. If this doesn't apply then that software should stay in the testing, or unstable versions.
And with respect to developing Debian's own desktop, XFCE's latest contribution are disappointing to say the least, and there are shortcomings with a number of the other desktops. Stability is increased if Debian has its own desktop.