Yeah, that's really a good one. I use similar patterns and it helps a lot. Also, you might want to vary the order of the fingers (left hand) :
Just try every possibilities.
And what's useful and much harder to do is to skip strings while playing (as opposed to straight-forward fast picking).
Look at the Severed Savior's "One by One" intro (I posted the tab on this site), it'll give you an idea.
Also, some good bands to check out if you want to practice fast picking without sounding boring (you can finds tabs for them easily):
-old Cannibal Corpse
Quo Vadis has got some insane fast picking. So do most of today's metal bands.