Hello!
Here’s an idea how to solve that issue:
Give the Layer panel in model space a second ‘local’ layer visibility flag (lightbulb icon) - just like Detail viewports already have!
After all, both makes sense: turning off a layer locally or globally.
‘Local’ of course toggles visibility only in this viewport/detail (which is remembered per viewport - just like it is in Details).
‘Global’ toggles layer visibility in ALL viewports/details.
In other words, model viewports should just be equal to detail viewports - 2 visibiltity flags!
To repeat what the problem is: one sets up Layouts nicely, with the right layers turned on. Yet once work is continued in model space, it is almost inevitable not to turn layers on/off - which messes up the Layouts!
If in model space this new local visibility flag is used instead of the global one - problem solved!
Please think about it! This might actually be a good idea. It would be one puzzle piece in the overall picture of improving layouting capabilities.
Sincere thanks!