OEMs need to quit convincing themselves they know how to create a UI better than google or the community. I have yet to see anyone that can and not make it unobtrusive, not annoying or not laggy. If they want to do that, they need to go the route of the market launcher apps like go launcher or adw and let users switch it out, instead of baking it into the device. Obviously Amazon would never do that because this device was intended by them to only serve up their content and no one else's (just looking at the way they removed settings from the OS gives that idea if the lack of google services did not). At least they did not lock it down to the point that someone cannot mod it
As stated, 512MB would be more than enough for anything other than what amazon did. If someone made stock version of android for it, this device would run great all around.