I have like 24 people on my friends list, 95% of which I rarely ever chat to or am able to catch them online to visit their town, so apart from one guy I went to uni with, would it be wise to delete all the other people on my FL?
24 people isn't that much, but you should delete the people you don't talk/play with anymore anyways.
I have over 60 so I probably should delete at least half of those people.
I honestly do not see why you would do that with only 24 people on your list. That really is not that much. I would say yes when your friendlist was filled until around 90 friends and more but it is not really necessary to do that right now.
I had 100 friends and clearing that out took so much more time than clearing 66 people that I ended up adding after that. I would suggest wiping it clean.
If you ever do it again in the future but want to keep some people, I would suggest writing down their FCs just in case you accidentally delete them.