But you have to grab anything to move and possibly snap it anywhere. To me it seems you want to be snapping is the default behavior then instead of simple positioning the selected object or vertex to the cursor position by leftklicking.
But if you have grabed any object or vertex, leftklick does no more set the 3d cursor anyway, as far as you don’t double leftklick.
Positioning the 3d cursor by leftklick only happens if no action is currently active and you are leftklicking to an empty 3d view space.
And the 3d cursor will be still placed by leftklicking to an empty 3d view space when things are organiced like you suggested it, if I get you right.
I can’t tell if it’s hard to implement this, I’m not familiar in Blender development.
I’m just thinking about this “problem” how leftklick may be better used, too.
Anyways, changing “leftklick” to “SHIFT & LK” or “CTRL & LK” to place the 3d cursor, and to avoid placing it accidently, seems to be a good idea to me.
Snapping by default is allready available by activating the magnet symbol. Therefore LK does’nt need to be changed at all to get this behavior, I guess.
So after all simple LK seems still free to be used for anything else.
May I suggest to use it for, let’s say… “select” ? No I don’t. ;D
EDIT - Sorry I’d get you wrong. You don’t wanted snapping by default but by holding LMB and confirm snapping by releasing it. LMB & CTRL to place an object at the cursor position whithout snapping. I’m a bit confused.
But this still does’nt necessarily need to affect “LMB -> placing 3d cursor”, because its only needed if anything (object or vertex) is selected. In this case LMB won’t place the 3d curser anyways, but would confirm a translate action, for example.