Really hard to choose, with such quantity of amazing instrumental parts, but I wouldn't actually concentrate on what is hardest to play but on what for me is most interesting to hear in terms of instrumental arrangements:
I am a bassist, I toy a bit with acoustic guitar and sing, but bass is my basic instrument.
Basslines have been such an important driving force in NMA's music that I think they are one of the most bass-driven bands I know of. And for that I think the most deserving person is Stuart Morrow, 'cause he set it up as a standard and whoever came later had some enormous shoes to fill. I wouldn't go far in trying to explain to a non-musician his technique, but those of you who do play, especially, bass, will understand what I mean when I say this: to me he stands so high in what he does with pick-playing as Jaco does in terms of fingerpicking!
Now, as for the single bass line that stands out I really don't know... It's the whole style that he brought, the position of the bass in the soundscape... From Betcha on, through Running in the Rain, Notice me, Smalltown England, Christian Militia, Vengeance... I love and respect all other bassists that came later, Moose - the whole T&C, my favourite album, White Coats, The Charge, what can one say... Nelson - Listen to Here Comes The War, One of the Chosen, Rivers, Brother... Ceri - Strogoula, The Weather...
As for drums, they are always great, but what will always stay my favourite drum tracks are Rob's Inheritance, Here Comes The War, Ballad of Bodmin Pill, Green and Grey, 125 mph and Michael's Wonderful way to go...
Acoustic guitar: Green and Grey, Higher Wall, Family Life...
Electric Guitar: many different small touches scattered all over... Intro on Archway Towers, the whole Love of Hopeless Causes, with Bad Old World at the top...
Violin on Vagabonds
Keyboards on Nothing Touches...
