I think his issue was that he was too foreign to the plot to really make you want to watch him. He was the only one in the group that had no link or stakes in the trip.
Rapunzel was obviously after her destiny and Eugene had to come along as her lover. Cassandra was there to protect her due to their friendship and had the most development out of the cast during the trip. Lance is Eugene's friend and muscle so he had to come along. Pascal is Rapunzel's best buddy so he also came along to help her, and Shorty was there to provide comic relief in all tense moments along with some much needed chaos.
Hookfoot was on the level of Max and Fidella in that he had no stake and no reason to travel with them. If he had been linked to the plot, I think it would have helped him a lot. I yawned whenever I realized it was a Hookfoot episode because I knew it was going to be filler centered around him and whatever happened, wouldn't impact the rest of the plot at all.
I think even Maximus had more of a stake due to his justice boner. And I enjoyed the Eugene and Max in the peril seas or whatever it's called because Max got a neat personality.>>107948069
Would never work. Vex doesn't seem like the booksmart type and would bore Varian easily. She may be able to beat Varian into submission, but there would be no real chemistry.