I take one or two tubes, a patch kit, and int he patch kit, several glueless patches, which are useless over the long term but if yo get three flats in one ride, you probably would rather stick on a tube band-aid than sit by the side of the road messing with glue. I know I would.
I carry a mini-pump because even if I rarely use it, I have had rides where I have had multiple flats, and it flat sucks .... but it sucks worse if you have patched tubes you cannot inflate because you only brought two CO2 charges.
Otherwise ... pretty much everyone brings the same things because those are what you will need.