Just keep on keeping on. It’ll all compound. 
Looking at my heatmap, I haven’t had less than 100 reviews a day since level 8.
It does in part depend on how you do lessons. If you take your time adding new lessons, and only do small batches a day, your reviews will always be nice and light.
Conversely, if you do all your lessons in one day, you’re more likely to hit empty patches before that annoying spike hits.
I always spread my lessons while still mostly doing 7 day levels, so it’s not like spreading lessons has any negative effect on speed. For me it just makes reviewing less annoying, and I retain the items better because my brain doesn’t effectively memorise 70 items in one session.
Nothing wrong with reorder as long as you use it sensibly. I’ve used it for the vast majority of levels, but I’ve never once skipped out on vocab. If you use reorder to reorder items, rather than a method to skip items, I don’t see a problem with it at all.
And there is of course never any reason to be waiting around on WK. So much important JP stuff to learn and so many resources linked on this forum. 