It sounds like you might be trying to burn your items before adding lessons. This would slow you down, but I wouldn’t say it’s wrong. You gotta do what works for you.
P.S. Japanese has a highly visible gamification culture to learning the language. Luckily, it’s not so large on these boards, which I’m glad about. Seriously, just do you! 
You should follow your own speed. If it feels a bit too slow, try experimenting a bit.
If you want some slow friends to hang with this might be the place for you!
I like to do 10 new lessons a day. I try do one batch of 10 each day, but if life is busy I only do reviews.
Often there are similar things in various items, vocabs that has same reading as the kanji and such, so getting the items out and having more than one similar item of same kanji and reading helps improve what you remember.
The SRS will help take care of the harder ones too, as they fall down where you see them more.
In burn it should be known fairly well. It is always possible to repeat them later (unburn items, whole levels and so on)
You should go at the pace that is most comfortable for you. But if you’re bothered by your current speed, increasing it a little for a while just to test how it goes can’t hurt. You can always go back to taking it slow if you don’t enjoy it.
It is completely normal to forget words. Heck, people even forget words in their native tongue. But I do think one of the things you may be “missing on” (or more correctly, delaying – and this is just a hypothesis) by going so slow is the extra reinforcement provided by the higher WK levels.
((Also postponing your ability to immerse in native content, which is arguably the most important form of reinforcement)).
I’m sure you have noticed that vocabulary, radicals and kanji using content you’ve already learnt keep appearing as you advance in levels – and what they’re doing (aside from teaching you brand new content) ends up also giving you more context and opportunities to cement the old in your memory. You could even say that they’re almost acting as new SRS substages.
Here’s an example. While Enlightened to Burn for, say, ‘ground’ may take 6 months, you are guaranteed to see it again over and over again in new lessons and their mnemonics. If you keep going at a decent (albeit not overwhelming) pace, you’re bound to see ‘ground’ in many more contexts and mnemonics than if you were to wait until you have mastered it – casually reinforcing the item in your memory without overburdening it.
That being said… Ultimately, everyone needs to find their own personal, manageable balance to strike between quantity and quality. Just don’t dismiss quantity as something that will solely make your life harder and experiment a bit to see if a slightly faster pace will better suit you.
Agree!!! I started in September and I’m still Lesson 5… IDK about you, but I tried to learn kanji the conventional way and it was awful so I can actually see the progress with wanikani… maybe just focus on your progress 
Going at any pace is better than going at no pace. I struggled with a fear of failure and not feeling like i’m not progressing which made me stop learning Japanese for a long time, but being so crippled by fear you don’t do anything so don’t make any progress.
Any progress, no matter how small will get you to your goal.
Do whatever you can, as often as you can and don’t worry about mistakes.