XFCE is super modular. You can turn off individual components. You can enable any program to start with the XFCE session. So, for example, disable xfdesktop an

XFCE is super modular. You can turn off individual components. You can enable any program to start with the XFCE session. So, for example, disable xfdesktop and xfwm; enable other window manager of your choice. Then, when you run xfce4-session via any mechanism you get all of XFCE, but with another window manager. You can pull up xfce4-settings manager to handle all system settings as you would in any other XFCE session. I am pretty sure that LXDE/LXQT allows this sort of modularity as well. I have no clue about KDE and Gnome. Of particular note, you can combine XFCE's panel applet with a tiling window manager. So then you can keep an application menu and notification area (with associated notification settings) from XFCE with an arbitrary window manager.