If I am going to have a prime in addition to a zoom, for me personally I want at least two stops of advantage.
yep, assuming the same range. The thing with the 35/2 and 24-70 is that they will conflict a lot. I shot with the 50 1.2 and 24-70F2.8VC for years and there was definitely conflict between the two. Nothing wrong with having both really, but you should fill missing gaps before you start building conflicting lenses. A 135/2, 70-200 should be on your list.
The 24-70 range is really disposable to me. 40/2.8, 35/2, 50/1.8, 24-105, 24-70mk1, 16-35, either of those, I would be comfortable replacing the zoom, however for events, the ooooh and aaaaaahs come from a short telephoto of sorts that can really isolate people. The wider zoom is for technical captures, nothing really inspiring there, really serving the purpose of grabbing the incidental environmental portraits and boring group shots.
70-200F2.8 of some sort is golden. Nice and simple. 135L, even simpler, but requires a bit of experience. I've seen many give up on it, but I'de say it's phenomenal. If I want some mind blowing portraits/candids, that's the goto lens.


