block slicer / layout Creation Mode - custom page layouts

u see the blue line here? indicating the blocks grouping layout. what if we had a mode specifically for layout creation, clicking on it would reduce the opacity of all text and images etc. and show all blue lines indicating the blocks and the current layouts, and then a user has three tools. select (which selects blocks), eraser which erases blocks, and the knive which will be used to cut blocks as example and they make two. this will allow for very easy drawing of a plan, think of how architects create a house plan @Michael_v_H ;) , but in this case just draw all the lines for the blocks layout. without having to do so for the outsides of the page ofc.

this with the ability to save this as a custom page layout would be nice, for the custom object types, but this requires also being able to assign where properties, images etc go.

in other images i have example usecases.