It seemed a straightforward thing for me to try about two weeks ago, but without success. I removed LXQT and LightDM, then installed Cinnamon. The system booted, then stopped at a grey screen. I'm sure there's something I failed to remove in the beginning or didn't install with Cinnamon, but haven't figured out yet.
For my next attempt, I'm putting Indian Summer on a USB stick and looking at its configuration. Perhaps I can strip my main system again and install a working Cinnamon...