I play mostly metal and have to agree. In my riffs I used a lot of different picking attack. I'll picking softly and concetrate on accuracy when doing some in between licks or in my solos.

Also, I don't pick the same way in rythmn and solos. In rythmn I'll attack with my pick slightly rotate forward while I'll do the opposite in solos.

I don't know why but it works for me. I also use fingers motions to pick and almost never use my wrist, except for accoustic guitar.