I held off on installing Double-Check for a long time, and it’s still nowhere close to my most used script.
What I really miss are:
[Userscript] WaniKani Lesson Filter
[Userscript] ConfusionGuesser
[UserScript] WaniKani Fast Abridged Wrong/Multiple Answer
[Userscript] Stroke Order Diagram
[Userscript] Keisei 形声 Semantic-Phonetic Composition
Yes, most of those are not “essential” but they really worked well with my learning style and improved my retention.
It seems like WK is working to try to get something like Semantic-Phonetic Composition included in some item pages:
but the script did it much better.
And, I’ll be honest, I still don’t really understand why WK doesn’t natively include stroke order for kanji anywhere.