@ hit9918
Allright! I think I finally understand what you mean. 
Indeed, arpeggios were not used that much by Japanese composers.
But I do feel a bit silly now, having compiled this big list of examples 'cause you said rock/metal but actually meant something entirely different. 
@ Grauw
Exactly, that's what I thought, too. 
But I don't think there is any effect at 0:23. It's just a string of notes played swiftly in a row.
@JohnHassink,
what is my point. how to make the point "westerner makes more western music" 
I found it: melody is one thing, the other thing is the chip hack.
western is more chip hack.
A lot of western composers (eg. Wolf) focus too much on the "sound design", and indeed not so much on melody and harmony (ie. the music ). I've been saying this for years, so I'm glad to find someone who agrees
Now I'm a bit confused. I'd say that Wolf's music generally is actually quite straightforward and 'clear', and hardly (if ever) makes use of 'effects' like arpeggios and HW envelopes (which I guess qualify as being more "sound design"- than actual composition related).
Should I think more along the lines of a certain "oomph" that music may or may not have?
I guess it's pretty abstract material, anyway.
But I'm genuinely interested in both your points of view.
Yes, Japanese music seems to be less restricted by genre borders. The Japanese (black) metal band "Sigh" is another good example, I guess. And a lot of game music can't be pinned down within one particular style.
And yeah, I noticed this "Baby Metal" rapidly becoming the hottest new thing among my fellow otakus.
