One of the nifty things about AS3 was that it was quite easy to associate a Class with an on-screen graphical object, aka MovieClip. There was a one-to-one correspondence between the graphical object and the code. And the you created a new graphical object (new WidgetBot, e.g.) and added it to the stage, it's class (for example event listeners, data structures, etc) was already set up to work with it.
Again, this may be a non-starter in the JS world, and if so please don't down-vote me -- it was the way to do things in the AS3 world, and it was a great way to keep code organised. I was just wondering whether any of this could be translated here.