My proposal is to have at least icons for Std_TransformManip, Recompute, Mark to recompute and Rename.
The first one a normal menu entry and there is no reason why this one should not get an icon, the other 3 would help in the context menus to quickly find them.
For Recompute we already have an icon: https://wiki.freecadweb.org/Std_Refresh, so this should be taken as basis for the new Mark to recompute icon.