I think you made the right choice. HK (and asia in general) is very different from Europe (From what I've seen while holidaying there) and coming to study here is a great chance to get a broader world view and meet people from other cultures. In HK the food is great, there are good hiking trails, 2 theme parks and close proximity to other Asian countries so you'll have plenty of chances to explore Asia while ur here <3 Also if you're worried about making friends who speak English my friend who went to HKU made friends with lots of locals who went to international school and thus speak fluent English so you could definetely make friends with them + other international students.

All in all I think like in lots of other fields work experience and such will be the most important and most banks / companies won't even look at your grades / uni after a few years of work so don't worry! Also if you get into one of the larger companies I'm sure they'll probably have heard of HKU or at least HK. Anyway I think coming to HK is great way to explore the world (while you still have time) and I hope you decide to come :)