Most all ball pythons fade and change with time. There are a few standout mutations that are resistant such as Monarch, Ultramel, and Desert Ghost and others.
Regarding Candy vs Lavender: The adult Candys I have seen develop into more of a light brown where as the Lavenders pull in subtle purples. It’s all subjective but I think a good quality adult Lavender beats a Candy personally. From an investment / supply standpoint Lavender wins as well due to Candy being allelic with the common albino. Justin Kobylka wrote his opinion on it in 2015 here:
Justin also gave some solid insight as to certain dominant mutations added into the dreamsicle help longevity:
" Brightest as babies
- Pastel YB Dream (less orange as baby, but this is the best looking adult Dreamsicle hands down!)
- ODYB Dream
- YB Dream (only 10% less bright than with OD)
- OD Dream
- Dream
- Pastel Dream (more yellow as baby, but way brighter colors as adults than reg Dreams)"
I think Pastel helps with dreamsicle longevity, which is part of the reason why I targeted one for my first dreamsicle, but may actually make them less bright as babies. This pastel dreamsicle girl is around 600ish grams (haven’t weighed her yet, just got her):
