I put a lot of time into creating an experience for my first serial site The Cathari Treasure and am not sure the effort paid off. The wordpress.org site has a customized theme that views like a book and displays unique backgrounds and featured images for each post. For all of the effort I am not sure the experience was an added draw with one exception, "podcast". I always record my writing for self edit and my friend convinced me to podcast. My serials now have more podcast subscribers than readers. The podcast have also garnered more attention for my serial as a webserial. So far other serial sites have not provided that benefit.
Learning from my first, my new serial The Potter's Daughter is a much simpler approach with minimal artwork and due to the genre I recently followed SGL's recommendation from the “How to Rock Wattpad for Your Serial Fiction” article earlier this year and have seen some great numbers so far.
Since I originally started my serial to solicit attention from agents and publishers I am not sure if I will continue alone. Including analytics in agent queries and directing them to a beautiful site has not seemed to have a short-term result.
I definitely will be keeping a pulse on the collective platforms to see what type of publishing success blooms.