Can I change BSP collision channel and delete built in channels?

I am trying to make a very simple game, and I don’t need all these extra channels to make things overlycomplicated like WorldStatic/WorldDynamic, vehicle, etc. I want to use custom made channels and delete the ones built in, but I don’t seem to be able to in project settings, I can only delete custom ones. Also, after deleting all the premade collision setups, my BSPs no longer have collision.