Buttons which run Set LISTERCMD=OnTopOn and Set LISTERCMD=OnTopOff can be put on the toolbar to turn keep-on-top on and off more conveniently.
For a toggle button:
@if:Set LISTERCMD=OnTopOn
Set LISTERCMD=OnTopOff
@if:Else
Set LISTERCMD=OnTopOn
(How to add buttons from this forum to your toolbars in case it is needed.)