While I do think you're doing a fantastic job in general, some of those TL notes sure had an unnecessary keikaku tinge to them. Any time you have to explain a loanword should raise an automatic red flag. "Madonna" too ambiguous? Fine, use "diva", no need to cling to the original katakana term if that's what it was. Sensei means "master" in this context ? Just go with "master" then.
It's a good rule of thumb that if it feels like you're putting too much effort into explaining a regular word, then that's exactly what it is. It's odd that you translate slang and dialects so effortlessly (again, great job there) but trip up on the basic stuff.