vineyard trellis

We are doing a test vineyard to see which varieties grow best before planting a much larger area with the "winners". How many varieties should we start with? We narrowed down our choices but still have 8 white and 10 red varieties we really want to try. The amount of research we put in is...

Other than actually staying up and lasting a long time, what's the most important aspect of a grape trellis? (I'm making a "trellis making" video for my YouTube channel and thought I might get some better insights here. Thanks in advance!