I am not fussy about colour, as different colours strike me when I see them. I am new enough to the "serious" betta hobby that I'm not familiar with all of the available colour combos. I'm kind of like a kid in a candy store.
With finnage it's the same. I already have a crown, a rose and an HM. For me a "want" would be the combination of finnage and the colours that highlight it. I like butterfly with crowntail or halfmoon.
My big wish right now is a giant with HM or plakat. Colour? Dragon or butterfly. Marbles are nice too.
Before I get my giant I'm waiting for this guy to come from the transhipper: