Here’s a massive list of scripts you can check out:
The WaniKani reorder script is a popular one (allows you to reorder radicals, kanji + vocab in any order and by level, helps prioritize lessons and reviews that matter in level up time) (this can be abused though and can cause a massive backlog of vocab lessons so use wisely ^^)
Also there’s the WaniKani override script, allows you to ignore incorrect answers (useful for typos and such)
Hmm… I don’t really use scripts, but I’m sure there are a bunch of other useful ones that can make your experience on WK efficient and tailored to your liking 