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The main problem with creating a good experience based on a live CD spin is that there is just not enough room, so the focus is always "what can we cut out to make it fit", not "what can we add to make it better".
The only way to overcome this would be to solve the 'localized spins' problem, ie find a way to install only a subset of languages. In testing before F10, I've found a English-only live CD to weigh around 440M, compared to 700M for a live CD with all languages.
Another argument for moving the focus from live CD to live USB is that many modern laptops don't have CD drives anymore.