I never heard about it being intended as part of a collegiate system: however I do know it was built in Tutor times by the
English so any responsibility for building work (or lack of it) falls squarely on Sasanaigh shoulders! lol.
TCD is I believe the only university (apart from Oxbridge) in the UK or Ireland to have a copyright library. It has some link still with Ox and Cam and generally follows their examination systems, term timetables etc. fairly closely.
Its reputation only really comes into its own when dealing with people from outside ireland. Here a TCD degree is not really viewed more favourably than one from one of the NUI universities (UCD, Maynooth, Cork, UCG etc).
Its kinda set apart from the other universities though. Its (marginally) harder to get into and you don't need to have passed Leaving Cert Irish to do so. Its typical degree course is 4 years as against 3 elsewhere (although this does not necessarily mean the course is longer or more comprehensive).
It does have bag loads of tradition though: cobbled courtyards, dinners, ceremony
plus I'm told TCD still have the right to hang one Catholic per year, though that may just be an urban myth!
I am currently at UCD and have lived in Dublin all my life. If there is anything I can help you with in terms of info about Dublin, the Irish system, Trinity, UCD etc. just PM me or post it here.