What if you change your mind at the very end? Causes a lot of problems.
Uhm, this is not the problem. I only want more workflow possibilities. For example, if I apply a subsurf modifier, the control over the mesh becomes very hard. If I apply an array modifier, I canât review the settings. On the other hand in this way I can do both things: edit the final mesh and modify some setting of the previous blocks.
That is a possibility (not allowing the editing of topology), so things could be predictable, but in that case Freemind has a point with renaming it shape edit since it wouldnât be a full fledged editing like in editmode).
The question then is how do you go from the base editmode with all the tools available to the shape edit editing and disabling a bunch of the tools and then have Blender know where you are when it comes to editing, I personally think the control-# method may be a little clunky, the UI design would actually allow for something like a mini-browser for modifier names where you can enable shape editing and select the level you want in the UI (like how you select materials and textures you want to edit in the UI right now).
But of course like you suggested the shape editing on any level but the base will have to be limited to now allow topology changes and disable tools that do change topology when used because of predictability issues otherwise.
You might be wondering if the predictability issues have been seen with other tools that have come into Blender, in fact they have been seen when 2.5 recently got initial functionality to sculpt on meshes using modifiers.