This was going to be my comment as well.. I tend to prefer cdnjs for as much as possible, since it seems to be the most diverse CDN in terms of supported libraries.
Though I've been trending away from using most libraries separately and bundling... may need to think about breaking things out again. For the most part, however, most of my bundle sizes are pretty small. React in dev, Preact for prod is the biggest mix... checking bundle size before/after adding a module (some will add a huge dependency tree).
There's no substitution for being judicious... and imho, even if you have to look it up frequently, using the DOM is usually better than loading in jQuery... even if you center around Array.from(document.querySelectorAll('...')) as your main usage.
[edited, with thanks to delinka]