Mmm hard answer, obviously hardy, and vigorous. I like big and flashy, and colour.
I like the form and size on flavas, i had a really nice ruglli clone that was tall substantial and had a vigorous branching habbit, which led to nice dense pitcher stands, ha an ornata that was very similar in habbit heavily lined with stark definition.... funny thing was that when i started out flava had little interest for me, but it grew on me hahaha. I also like the really stand out colours, like the purple blacks and strong contrasty ones such as your willisii x leuc clone. Im not a huge fan of the weird pitcher shapes... psiticina is at the bottom of my list hahaha. Lemme see if i can grab photos..
I'm a big fan of Purpurea's due to the interactive growing of them. Meaning I have to fill them up with water like once every few days during the summer, give me a excuse to stare at them more. I also like how you can see the bugs being captured and drowned... Dark but cool.
So I look for the low growing types of sarracenia or open hooded ones.
I prefer plants with splashes of colour or lack there if of.