Also bear in mind that with some color mutations, the cere is not the typical blue or brown. Twigs for example is a recessive pied, and he is at least 2 yrs. old (?), DNA'd male, and kept the same pink/purple cere and dark eyes of the juvenile.
I've never had a female Budgie, but I've heard that they don't sing (go on and on twittering) as much as the males do. Males are typically very noisy.