Too late to the conversation :(
It seems as thought there could be technical improvements - for example the rezzing seems random sometimes; where it would be better if the closest appeared first and expanded outwards. However, I'm guessing there has been plenty of experimentation by LL technicians.
If the product is what it is, then the main thing that you can do is improve information to the user:
* Qarl's suggestion; start with all shapes with default texture then fill-in with actual textures.
* Loading screen showing progress bar that doesn't show the scene until all has downloaded, but with a button to optionally jump straight in mid-download (managing user expectation).
* Permanent on-screen download indicator showing progress as you move around.
This is all viewer-side stuff though, and there's nothing stopping a 3rd-party adding it in.