I can understand your reluctance to move to a small town as I had to live in a few while working over in England myself. However, experiencing "city-life" is one thing, getting the degree you desire is another and this is where compromises have to be made. After you finish your degree, you’ll have plenty of time left to experience "city-life" and Carlow is a rapidly growing town to say the least.
You also say that you dropped out of honours maths & physics. Considering that you need at least two honours subjects for any course, what honours subjects are you doing? If anything, I would have focussed on honours maths & physics and done the rest as pass subjects. If you are pretty competent with your maths, then you should be OK going to third level with a very good mark at the ordinary paper, but it’ll still leave you with that little bit extra work to do when you go into 3rd level.
I had a look at the LIT course. While it looks the more or less equivalent to most CS courses, I can’t comment on how good it is myself. Maybe someone else on the forums can help you out there.
My final piece of advice to you would be not to rush into things. The quality and choice of your degree are going to be with you for the rest of your life. For this reason, think long and hard about your choices and choose wisely.
If Carlow is your first choice, then compromises are going to have to be made!! Why settle for second best??