I've been playing around a lot with the Gallery APIs but one thing that really annoys me is the jQuery dependency. This makes the API not really ready to be used in the modern front-end frameworks such as Vue.js, Angular and React. Therefore I went ahead and re-wrote parts of the API and removed the jQuery dependency - I also started making use of Async/Await to handle Promises. I know there's not complete browser support for this feature yet but the main ones support it now (Chrome and Firefox). I published all of this to NPM:
Admin API: https://www.npmjs.com/package/alteryx-admin-api
Subscription API: https://www.npmjs.com/package/alteryx-subscription-api
Using the Gallery API is now as simple as 'npm i alteryx-admin-api' or 'npm i alteryx-subscription-api'.
No need to play with files on CDNs or the oAuth file - this is now a dependency that is automatically installed when you run the above installation.