Andrew, we all have questions about stuff. I don't understand anything technical whatsoever so I just read up....then decide I still don't understand and go look at pretty pictures.
I think the point everyone is trying to make is that you should make the most of what you have, not look for faults and issues ( that don't actually exist ) all the time or you'll never get on. I enjoyed my old xf1 - it was £120 worth of point and shoot with a small sensor and poop at anything over iso800 but I learnt to use it, I didn't constantly pixel peep and go " oh, FFS this is crap ".
You have bought an awesome camera with amazing lenses - have no doubt in their ability. Many people would give their left arm for this combo. Just use them and learn how to get the best from them and you'll be fine.
Enjoy