The criticism about voter relevance is fair, but I wonder if this is still useful for a different purpose: training your own eye for landing page design.

When I've tried to improve at visual design, the hardest part was developing taste. Comparing options side-by-side and articulating why one is better is exactly how you build that skill. The aggregate rankings matter less than the act of judging.

Have you considered adding a "why did you choose this one?" prompt to collect qualitative reasoning alongside the votes?