Nepenthesis
Formerly known as Pineapple
Well, it's not like you are going to have much of a say in the matter: when a plant gets old enough to vine, you are gonna get uppers! Best to educate yourself now (before buying a boatload of plants) to learn which ones will produce the kind of uppers you wil like, and which ones you don't. People grow N. lowii because they want the uppers. Others, like N. maxima produce rather plain uppers lacking marking and color, other than green.
I looked up the upper pitchers of all of the neps I own. Luckily I like them all, and most of them are colorful uppers. I believe the picture that I bought my ventricosa x talangensis from was the picture of the upper pitcher judging by the shape, and that plant is already vining, probably over 16" tall already and growing fast. I should be getting uppers on it soon.
I think the maxima's upper pitcher looks kinda cool though. It's a neat shape, despite being green, and it's not just a green flower... It's a green flower filled with digestive juices that eats bugs!