Following on from nbohr1more's comment -
Where did you get 14k as the brush limit? If that's confirmed in testing then we should add it to the limits wiki.
I found that figure after several days work & testing on the very large city map, when the map hit 33k it would instantly crash to desktop with malloc errors. had to get it down to 15k before it would stop crashing.
As Goldwell pointed out I have created other large maps that have gotten close to 33k but they were fine, so as Obs pointed out the conclusion is that the engine is splitting brushes at compile time exponentially increasing the number of brushes.
Edited by Bikerdude, 20 April 2018 - 03:43 AM.