In fact if you notice any image not reliably preloading, tell me about it here. When you pull a mob, use a skill, cast a spell, etc. You shouldn't see the outline of an image loading. I spent a lot of time and effort to prevent this. That's the whole point of loading time.
In any case, I did notice a difference when I logged in quickly to check. Seems to work WAY better now and I'm sad to know it was this bad for this long (there was a bug).