Cache the bundles?

It’s quite annoying having to re-download the bundles every time and can only be a waste of bandwidth. A simple checksum check could work in the same way the Lua cache is handled for GMod?

You don’t download them, just load them from a cache located on your computer.

As far as i have heard the browser handles the caching, But it isn’t working on some browsers. I think it just hasn’t been working on chrome for some users so I would try another browser if you care enough about it.

Unfortunately you do download them:

" The WebPlayer shared cache allows up to 50 MB of cached AssetBundles."

The game has more than 50 mb needed to be cached. Garry doesn’t want to pay for a caching license.
Browsers can handle the caching usually though.

I’d love to see a breakdown of the assets by size, ie. how much of it is audio, textures. There are two things that could happen. The most obvious is to progressively stream assets (have a minimum base set of assets required, launch the game, stream assets in prioritised by size on screen to player, larger audio clips like music can be faded in when loaded), the second is to use Substance for textures where appropriate.