The experience is pretty similar at all colleges (there’s pros and cons everywhere) so the things you should really be thinking about is what type of accommodation you want and then put colleges with what you want at the top. For example, if you want self-catered and gowned make sure your top five choices are self-catered and gowned. All the people who I know got a college way down their list didn’t submit the form in time or only wanted to go to super competitive colleges. So decide on a couple that you like and keep them at the top and you should get one of them. In the end, everyone ends up liking the college they get so don’t stress if you don’t get what you initially wanted.
Also in terms of old vibes you could always take a look around Durham itself bc even if you don’t live in an older college you’ll still be around old buildings. I actually prefer it that way bc the newer colleges have nicer accommodation.