How should this be determined? Go by total weapon type slots. A Mech with 8 laser points can only use 6 (or 4, whatever) of the same type before facing the penalty. After that the 7th and 8th weapon will increase ALL heat of the same type by 10-25% depending on the type (larger weapons = higher penalty). And when I mean same type I mean specific weapon, like ERLLs or ERMLs.
You could then add some more skills to the operations tree that will let you boat more weapons (+1 to max same weapons type for example), or you could simply make certain mechs themselves have more play with this sort of thing (i'm thinking about the 42 laser point medium clan mechs).
I guess to take it easy on mechs that have few weapon points of a certain(2 or less.. or total combined of 6 or less or something) they would be exempt from these shenanigans.
Just a thought.
Edited by Nine-Ball, 06 December 2017 - 11:27 AM.