So to put this as succinctly as possible, I’ve been studying Japanese on my own as more of a hobby than anything else for about 3 1/2 years but not constantly in that time. During the first year and a half or so I was doing every day Wanikani, little bit of Duolingo. I know that’s not ideal, but I used it when I couldn’t get to Wanikani that day and I mostly focused on Kanji/reading, so I had an extremely consistent routine of review and learning new kanji and vocabulary for a long time. Then, whether it was from burnout or other things in life getting in the way, I kind of put it to the side and while I did do small refreshers every couple days, since then I haven’t been consistent with it, and I feel like my vocabulary has slipped. I’m forgetting kanji readings that I used to know, and I think I wanna go back to doing regular study, but one of the reasons why I’ve been so hesitant to go back to Wanikani is because I need to go and relearn a bunch of burned items, but I have so many burned kanji/vocab now that I don’t know where to start in terms of reviving the right ones while letting the ones I still know stay burned. I’ve used tampermonkey extensions to kind of streamline the experience and add features to WK in the past, so I’m definitely gonna see if I can update those. I’m wondering if anyone here has any experience with getting back into this and could help me find a way to make it more manageable and to not be burned out as much this time. I’m at around level 23. I know that I need to immerse more, for sure, but when it comes to specifically learning new kanji and words, I need to find a more manageable routine. The amount of backlogged reviews and new items to learn became too much as it bloated with every level.
I have a lot of experience with this – fell off many times, but always ended up returning – sometimes with reset and sometimes without.
Took me waaaaaaaaaaaaaay too long to reach level 60 (8 years, to be precise), but I managed to do it.
My advice is to keep moving. It’s better to reset to level 1 and have to relearn everything you’ve learned, but start moving – than to keep sitting in front of evergrowing pile of reviews, trying to muster the courage to tackle it.
Now, if you can start doing it right now without a reset – that’s great, but if you can’t, reset is a good option. Not necessarily to levle one, but to the level you are comfortable with.
I know, it feels very frustrating to have to relearn items you’ve once burned, but the thing is – if you don’t remember a burned item – then it’s not really burned and by unburning it you wouldn’t be losing anything, you would just admitting that you don’t remember it.
And if you do remember the burned item – then unburning it would mean burning it even better, so that this would be an item you’d be absolutely sure of.
That being said, there are some scripts that let you unburn only specific items, so if you can clearly determine which items you remember well, it would certainly make sense to let them stay burned. I’ve never used such scripts myself though, so I don’t know much about them other than that they exist.
Once you get back into doing your reviews again (whether with or without a reset), the way to manage the pace is to manage how much lessons you do. While it’s tempting to learn all the lessons you get right away, it would also mean getting them all at once later as reviews, so if you want a slower pace, you should limit how much lessons you do per day and in some cases might even decide to stop doing lessons for a while until the amount of reviews gets smaller.
Now that you have begun reading and listening, specifically learning new kanji and words – has become less important. I mean, it is still important and a great minimal daily routine, but you now have an alternative source – which is reading and listening, and eventually its role would become bigger and bigger and WK would start gradually becoming more and more of a supplementary resource (while still providing the core – the minimal daily routine).
Anyway, sorry, I hope this was at least a bit helpful. In any case, best of luck with your studies! 
I totally agree with everything trunklayer said! For what its worth, what has worked for me is choosing the number of reviews I’m comfortable with (at the moment its about 100 a day) and using the review forecast feature to guide when I should take on more lessons. If I see that tomorrow already has more than 100 reviews scheduled, I usually don’t do any lessons that day so that I don’t get overwhelmed. I often have only 50-60 apprentice items, and even though its kinda slow it stops the reviews from feeling like a burden. Keeping WK relatively chill leaves mental space for other reading and watching Japanese content. As I read I do notice that I have forgotten some burnt items along the way and I just unburn them using the built in function on the website. I think some amount of re-learning is a part of the process of language learning?
Perhaps take a look at the Kakehashi app (iOS or Android), for which the developer is an active member of the WK community.
It is aware of your WK experience, but it allows you to do reviews outside of the WK SRS infrastructure, so that you can ease back in to what you may have forgotten from what you’ve learned in the past, without doing the formal SRS rigmarole.
It has much much more than that, too.