As I see it, you kinda have to work around what’s offered to you, meaning the barrels are a set specifications from the manufacturer. It’s not to often we can have a barrel made to our specifications. So, I usually work with what I have. There are many of time I’ve chopped barrels down, because A) the gas port is too big and B) there’s too much barrel after the gas port. I only install a expansion chamber type Comp/FH when the barrel is to short after the gas port. I like to run just FHs or non-expansion chambers Comps when running a proper length barrel. My biggest pet peeve with ventilated expansion chambers is the occasional fireball they produce every few rounds. I like my flash (or lack there of) as consistent as possible. The rest of the formula is working on adding or subtracting reciprocating mass, keeping it balanced around ammunition types.