I live in Leeds and go to Cam so will try and offer some help.
Like you, I applied to five big city unis plus Cam, so again it stood out. I have to say, however, that my reaction upon visiting was not the same as yours. The first time I came I knew I wanted to go - that was more noticeable to me than, god, isn't it small.
It can get a bit claustrophobic at times, but a day in London solves it (yes the trains back are an issue if its a night out in London you want - but chances are once here you will meet millions of people who live in the London area who you would be able to stay with. Apart from that, Cam does have a lot of what Leeds has, just on a much smaller scale. The cinema and theatre options of cam are better. Obv Leeds has better shopping (if that matters) but its only 8 weeks of the year anyway, and cam isnt as bad as it first appears once you find the grafton centre.
Main dif and once concerning you seems to be night life. There is a massive difference between the two cities on that point. A lot depends on what you are looking for from night life - for me, the most important thing is going somewhere where I know quite a lot of people, with music I can get drunk and dance to. The lack of choice of venue here, and the size of them, did come as a shock at first, but I've grown used to this already and am now perfectly happy with what Cam has to offer.
I can't really talk bout the academic sides of both unis, but I'm preety sure you would do more work in Cam.
In short, don't turn down Cam because:-
- There is nothing at all to do and everyone is boring (false)
- You will miss out on the best years or your life (I'm having them!)
Do turn it down if:-
- You are desperate for a city where there are more clubs than you will ever be able to go to (this is the only main dif)
- You hate small places and want to live in a really big city.
Any qs, feel free to PM