I say go all out. Just leave the trigger springs alone. I’ve cut the fuck out of m&p’ s & glock slides, changed out all sorts of internals and have only EVER had failure related to trigger springs. These guns are cheap and plentiful. And let’s be honest, if you don’t like it you can sell it probably for 75% or more, hell you could even make money if you think about it and market it right. (The world is full of impatient people, we all know gunsmith time is slower than the rest of the world) So it has the same diminishing returns as a stock or hardly modified with potential to turn a profit.