I’m going to make a refinement to what @tommo is saying - I think it’s important to push the speed up but don’t drill actual patterns you want to play too many times over and over sloppy. Try it at speed a few times and stop.
I’d say for trying to get speed down, have you started by finding a motion that lets you tremolo pick with no left hand involvement at Yngwie equivalent speeds? If not, then work on trying to find that, and see if it works across each open string. Not really focusing yet on string changes. Incorporate that as a daily exercise and make sure you can reliably and evenly hit speed on the open strings first.
Why would I say that? In my experience, practicing patterns too many times when you’re still trying to find your motion will have a tendency to mess with hand synchronization/tension and I’ve found that going back to pieces I learned before I could play them, but drilled them too many times sloppy, I have to unlearn the bad habits and it’s slower going.
Similar for crosspicking, I think if you have some dedicated exercise you want to use to just find the motion - that’s fine, but you might be better off doing open 3 string rolls (and maybe just muting them with the left hand for clarity) then only bringing in the left hand when you slow it down to clean things up.