I improved my productivity and productivity of my apps by dropping jQuery and other useless frameworks, and also prototypes totally. Only Vanilla JS, simple objects with tiny libraries instead.
Unfortunately I was very surprised that so many years later we still don't have a good Vanilla JS library and UI widgets without jQuery dependency and because of that I created BunnyJS - almost everything you need in every modern app, easy to get started and extend so you could use the code in any project.