Global Falloff Tool _Revisiting Proportional editing

I feel perhaps the one area of Blender modeling that is in dire need of upgrade is the proportional editing feature in Blender. It suffers some unfortunate limitations that make it unusable in several situations-

Limitations:

*Does not respect selections- Proportional editing affects selected and unselected elements just the same. Difficult to manipulate one part of mesh without affecting another part you don't wish to edit.

*Only useful for modeling transforms- not applicable in other areas of Blender where you wish to modulate other types of changes.

*No set range- No way to set a specific range for the proportional editing to take effect. Limited to a spherical range around the element/s being manipulated.

*Limited to a single shape for area of influence-spherical

*Not applicable to modifiers- it certainly would be useful to apply a falloff to something like a deform modifier, shrinkwrap, bevel, etc....

What I propose would be a global falloff tool that is drawn onto the screen, something like in pic 1. The wide end of the triangle would indicate 100% influence where the short end would be 0%. The green handles on the end can be snapped to geometric elements like points, polys or edges (whatever Blender's snapping system works with) Not just applicable to modeling operations, but you could set this global falloff when doing something like weight painting (pic 2)

Or even beveling an edge (pic 3)

Something like this tool would just be a linear falloff but you could also have different shapes such as radial or different shape falloffs, or even falloff by curves.

This also could be integrated into modifiers so that you could have a place in the modifier to draw out a falloff range for the modifiers affect. The advantage of course is that the falloff could be edited at any time while the modifier is still active.