BPs are wonderful pets. And I'm glad to see you looking into your snake instead of buying impulsively.

Sometiems snakes hiss. It really depends on the snake. My corn rattles his tail and hisses when you open his tank, but loves to be picked up and held (it's more a surprise thing I think). Others don't handle their snakes often so they aren't used to being held so they hiss. Some snakes are just hissers. My BP has been a sook from the frist moment that I got him.

When you do bring home your little guy, be sure to give him time to aclimatize to his tank. Which means no holding, touching, bothering for about a week. Then slowly start to handle them. I know it's hard as all you want to do is hold and touch and everything, but they are freaked out, and need time to settle down. Some people who have snakes that are very freaked out place something inside the tank that smells like them so the snakes get used to their smell (ie a face cloth that you carried around with you for several hours). With regualr handling most snakes should clam down.

As for patterning, it's all about what is pleasing to you. While I think some morphs are beautiful, I am not comfortable with the genetic inbreeding needed to attain them, so I plan on sticking with normal. And they themselves come with many different looks. It really all depends on you. Go with what you like, not what the general BP community at large likes, as it is your pet.