To answer one part:
You are right about the previous mozzie situation - 4 years ago I would be responsible for banishing around 4 or 5 of the pesky little blighters from our house each evening. Nowadays, 1 or 2 a week is more normal - one hell of an improvement.
You do seem to get certain places that get quite a few all at the same time, but I couldn't say it is one bar or restaurant, just any one now and again on a very random basis. It's rare too, but all you have to do is move on if it happens to you!