If you don’t know this thread The 0/0 streak challenge maybe try to get there, it will keep you motivated for doing at least a 0/0 for each level.
I am not that fast but I notice that I do all my reviews each days, I have the ultimate timeline userscript installed and I don’t want to see my day strike review going to 0.
My goal is to do between 20 / 30 lessons each days. But if I don’t do my lessons before my reviews, I procrastinate and I miss some days with 0 lessons at all.
So for me it’s better to do Lessons > then review. Maybe 10 lessons at morning, and 10 at the evening, it depends. But I know if I don’t do all of them before doing my massive pile of review every evening, I don’t do them at all ^^
I did it 
Level 9 done in 10 days 22 hours, last Pleasant level I am here !