Electrical – Is sealant recommended/required over receptacle or other ceiling fixtures located in attic

They chew, rather determinedly. Keeping them out when they want in is no small task, indeed. One approach with moderate success is to cover the opening with hardware cloth (heavy wire mesh) molded to fit and nailed carefully in place, and then spray foam. Board over the top if you like for appearances sake. The missing wood may well have been chewed away rather than knocked loose, given their usual mode of operation. Keep an eye out for new holes being chewed elsewhere on the house.

Here are my notes:

GFCI protection is required for all receptacles in unfinished basements (210.8(A)(5)).

Any habitable room in a basement may require an emergency escape route (see this answer for more detail), so check with the local building department. Note that "emergency escape", is slightly different than "egress" even though the terms are sometimes used interchangeably.

So the catch-22 here is. If you call it habitable space, you don't need GFCI protection, but you need an emergency escape route. If you call it an unfinished basement, you need GFCI, but not an emergency escape route.

As of NEC 2011 (I think), a grounded (neutral) is required at switch locations (404.2(C)). So only cap the neutral at the switch, and connect it at the junction.

The labeling is helpful if you are doing work in the future, but may not be helpful to another person that doesn't understand your labeling system.