Great to have people excited about visiting such an amazing area.
I have not climbed lots in the Darrans, but on all the routes that I have done I have only had a single set of cams and a single set of nuts. I don't carry gear bigger than a fist (3 camalot) but I have been glad to have tips size cams. A few extras doesn't do any harm - if you have the strength and enthusiasm to carry stuff, you can usually find a way to use it, but you could probably climb most of these routes without extra gear. You can solve most problems by climbing on or belaying early.