I’m rebuilding and extending my layout. In its previous version, apart from the track, ballast etc, all the scenery, buildings and so on more or less sat on top of the baseboard. I know that the tunnel though the hill needs to be made accessible in case of derailments but I am wondering how much should be stuck to the baseboard. I have retaining walls hold up an upper town scene, landscaped areas, viaduct and embankment and the hill with a tunnel though it.
The layout is permanent and not designed to be removed. Though in it previous version, having so much just sitting on the surface did make removing it and starting again much easier.
What do others do? Thank you.

