I don’t get it… If the section planes are hidden, they’re hidden… 
Anyway, have you tried adding a custom shortcut to “hide rest of model” ? It seems you’re experiencing lots of problems while editing your groups/components. I couldn’t work on sketchup without a shortcut on it. (there is no default shortcut for it). Try it out, If you need the context while editing a group, just toggle it on. Then toggle it off to concentrate on the group itself