May only say that, with a caveat of my own practice being much more limited, what Panpiper had said is true both from a practice and historician perspectives.
About New Zealand martial arts I've heard it highly recommended from a researcher in such things, too.
And to summarize a question on technics, as a master of my aquintance said: "All men have two arms and two legs. And nobody is able to bend knees backwards. So there are only a limited number of effective technics, used by most schools". (with a caveat of different things being stressed, of course - and weapons produced in local tradition can influence technics to a degree. Still, technics of a Chinese *dao* broadsword can be actually quite similar to those of a Scottish one
)