Agreed! And make it easy to revert to the style saved in SU scene after tweaking with other styles...

From your description not sure what you want. You just, say ,have a line and want to add a vertex along it? I don't get the dragging-and-adding description. This is one of the few things that LO CAN do. Double click on line, then click on it with the option key down.

Not concerned about objects getting out of order, not concerned with objects that are being moved. Merely concerned with 'altering' unique objects that must change shape to fit each other. E.g. "whoops we're 2' outside the zoning envelope, let's move everything back 2' from column line 'B'" Moving the columns is easy. But each floor, partition, wall, storefront group etc. must be opened and edited separately as necessary, moving only the faces which need to move, using an 'area select' and 'move' within each group. Just want to do this in one step. I bet if this were easy to do as a plugin it would have been done already.