In my opinion its all a matter of preference. And since there are 6 subspecies that look very different from one another and even look different among localities, that preference can be very specific.
((not getting into morphs))
Personally though I like all of them and think all of the sub-species are beautiful in their own ways. However, I like the diamond pythons ((M. s. spilota)) and the Inland carpet pythons ((M. s. metcalfei)) the most.
Either way, as I said, its all a matter of personal preference when dealing with localities and sub-species.
It is about personal preference, but in general you want a carpet that’s clean, bright, and has a high contrast.
I think this carpet is kind of ugly. That’s my personal opinion.
I think this carpet is gorgeous.
In the USA, most carpets are intergrades, so it’ll be hard to find a pure anything. Most of the really gorgeous carpets are mixed bloods anyways, so not many people seem to really care about it.
Also, when in doubt, ask for pictures of the parents. Carpets are extremely variable, they could hatch out as ugly ducklings that grow to be trophy animals… you never really know!