I practised Silat for a while, so I can help out a bit on that. Silat is about staying low/presenting a small target/moving fast whilst low (due to defending against invaders in tall grasses/crops), so a dodging buff would make sense. Silat also uses mostly large flat bladed weapons or fine daggers which are used to hack off or stab opponents, but none which would be common in New England. Even in the most kitted out training halls they wouldn’t have the proper equipment as you couldn’t really train with the real weapons (being far too sharp/basically used for hacking peoples legs/heads off). Most of the training we did was just general martial arts stick fighting, as there was no real point in learning the true Silat moves (which was why I moved on to a different martial art)
Most of it is quite specific (take the Kujang for instance) and has to be extremely well balanced, so couldn’t be easily substituted. The stick/staff weapons (like all martial arts uses) aren’t given much priority, so I doubt anyone would pick silat for them.
Systema/military fighting styles are a bit needless really, as they use any and all techniques to disable an opponent and don’t have proper ‘forms’. As in, I don’t see how you could implement them in anyway that wasn’t just that you were better at fighting.
Good luck with the expansion!