The rocket loads the animated gifs in on mouseover, but this is already too late to load a big png as the user is already interacting with the GUI.
It would be nice if the rocket was proactively rather than lazily loaded to avoid the half second or so of missing rocket on mouseover.
By the time I've read the article (videos, photos, overlay image library and all) I'm sure you could have loaded the rocket art without just doing it upfront and slowing first paint time.
I fully recognise that this is not a good use of the devs time, but it would improvem my interactions with the site.
Loving the update, though cliff explosives being so far down the tech tree is frustrating. <3