It's a good opportunity to experience what most people on Earth have to deal with. Please don't take it personally Simon, it's just that your compatriots tend to be the most entitled people I've met.
For 2, how often do you see Future Perfect Continuous or just Future Perfect anywhere outside of literary works?
I'd put grammar at much lower priority than vocabulary & common phrases, since knowing just a bunch of words (at least in most languages) can get you very far.
40 hours of flashcards and practice can cover maybe 90% of your typical tourist conversations for many languages. Where are you from? What is your name? What do you do? How much does it cost? Can you give me a discount?