City is very highly regarded, both in general terms and within aviation. Not quite world leading, but very good.
Regarding degrees - A DEGREE IS NOT A BACKUP. It may support your career, it may help progress into something else, it may develop skills that are very useful: but it is not a specific qualification.
If you want a backup, get a bookkeepers qualification, qualify as a lifeguard, do evening classes at catering college - in other words a specific skill.
Do a degree to enhance you and your career, or for the sheer interest of it. I did a part time PhD years back that I didn't need, but it opened a lot of doors for me - but it built on what I had (and was very interesting and rewarding), not acted as a backup to anything.
Part time makes a lot of sense for anybody who has a "real life", such as flying for an airline or as a flying instructor: if you are very disciplined it can be fitted in well with other activities. If I was looking at that, I'd start by looking at the (UK) Open University, or (US) Embry-Riddle, but there are certainly other organisations worth looking at. Just beware of the "certificate mills", which certainly exist, particularly in the USA, and will just take your money for a worthless piece of paper. Anywhere giving you significant credits for existing experience is probably in this last category.
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