Do you think that an open application increases my chances of getting accepted?
Those 3 are the first that come to mind for me.
As far as I know, it doesn't really matter what college you go to because it is the faculty that deals with the teaching and it is the college that organises tutorials.
I'd pick colleges on how they look and feel to you since that's where you spend most of your time.
Education quality is determined by the faculty not the college, so there's no worry there.