I’ve taken a pause on learning new items since I ended up having about 70-80 leeches following me and just constantly reappearing.
It means I’ve been on this level for about 15 days now without learning a new item. I am finding it’s helping for sure. In the meantime, I’ve started hitting BunPro and focussing on N5 grammar.
Does anyone else ever take breaks for a bit to clear down their leeches?
I’m not sure what you mean by “leeches”. 
I don’t think this is necessary, especially not at the lower levels. Around lv 40+, yes, it might be advisable to take a couple of times to focus less on learning new items, and more on the items you struggle to keep from falling down the SRS-levels. Putting time on leeches means getting rid of apprentice and guru numbers, which just makes review sessions shorter and easier.
Because guru reviews are slower to come around, I’d put 1 week or so on that sort of thing, before moving on to learn more items.
Also, with the new item picker method, you could also focus on “easier” items to not completely stop learning new material.
Many before have said they find it depressing to just focus on old items that you struggle with, and it is in a sense. Sometimes, adding some new items into that mix, just makes for a more enjoyable time reviewing -seeing as they might be easier for you - reminding you that it’s not that you’re bad at memorization, but rather struggle with some items. 
We all do! Remember that. Ganbatte! ^>^
Before the recent Daily Lessons change, I had two rules of thumb about lessons: I’d only do lessons unless/until
(That is, with my 5-item lesson batch size, if I had ≤ 105 items in Apprentice and < 375 forecast items at 3.75 days, I was good, if I had 450 at 4 days, I’d stop lessons until the situation resolved.)
This was less about tackling specific problems (I’ve become more and more Zen about that as I’ve gotten past Level 30; now I’m just ruthless with marking things wrong via the Double-Check script, even if I guess right, and let SRS magic take care of it) than about dealing with overload.
Since the Daily Lessons feature arrived, I’ve just been using it (for me, that means 15 lessons a day) without modification. I was skeptical, and assumed I’d at least want to make sure I get new-level Radicals out of the way faster than its algorithm does—but it seems to work much better than I’d have predicted. It has caused my queue to bop up above 120 Apprentice items from time to time, but my discipline before sometimes resulted in “wasted days” when I had as few as 60-ish Apprentice item in the queue.
I think I skipped the Daily Lessons on three separate days when I had particularly bad performance with lots of stuff slipping.
Next month I go on my first totally-offline vacation since starting WaniKani (thanks, pandemic), and I’m trying to decide whether to just keep going normally until I go offline or to ease off beforehand. I think it’ll depend on my precise level progress as I get close (right now it’s taking me about 20 days a level, which seems about right for a somewhat <15-a-day new-item average).
Vocab which you repeatedly get wrong, and continue to reappear for reviews. They’re called leeches since get stuck with you
Ah, thank you! Yeah, then I definitely prioritize learning those properly before taking on too much that’s newer — often that helps with others too!