Here you are.
The context is to get a set of icons for newly introduced Std_UserEditMode.
Obviously the first requirement is that each icon shall denote its own "name/function", respectively :
As a common requirement, they should also denote they are link to the feature "editing", so probably using some kind of pencil as a universal symbol could be right, as in Std_Edit.
Finally ideally, icons should commonly denote that they represent an "action mode", in the sense that no action is performed directly by selecting one or the other mode, but it influences how the software will behave.
You can eventually have a look at the temporary icons I used (they are copied from existing FC resources), which IMO are not so bad, but definitely not so good.
I pinged @bitacovir because he asked for a topic, but anybody that want to participate is welcome.