Is there an average word count for Tapas novels?
Nope. Tapas premium requires at least 80,000 and you tend to do better with longer novels, just because that's the general expectation of serial readers. But I currently have an ongoing novel that will be in total around 190,000 words (2 parts), I have a light novel that ended earlier this year with about 58,000, an ongoing novel that is just under 90,000 and book 1 of a 4-5 book series, and a short story that's around 10,000. I will say, though, that the only reason my short story has readers is because my novel readers check it out. It's almost impossible to find a short story on Tapas if you don't ask or aren't really searching for one.
My light novel was actually the most popular while it was running and had the most interaction, but obviously my longest novel has had more time to build a following.
As a novel writer, what is your usual word count per chapter do you post on your story?
I try to aim for 1500 but it depends entirely on the novel. One is a BL slice of life romance, so episodes are longer just because it's a slower story. If I go over 1800, I split the episode into two parts and post them both together. Sometimes an episode is only 12-1300 words.
For the light novel, I posted two-part episodes with each update, around 800-900 each part.
My fantasy has shorter episodes, 900-13/1400 words. My two current WIPs will also have this length episodes. It's enough to have things happen and reach a good episode ending, but short enough to read easily.
Whatever length you go with, the most important part is to have a satisfying episode. One where a) enough happens to make it a full episode and b) it has a clear cutoff going into the next episode. If I usually post 1600 words and an episode needs to end at 1200, I cut it at 1200. Sometimes I need 1900 words, and I just split it so the reader can choose if they want to read them together or not.
As a reader do you prefer longer or shorter word count per chapter?
Shorter word count, definitely (says the person writing longer episodes...). I like the 1,000 range. They are easier to read and as @shfra13 said, there is no bookmarking. It's also better for binging.
BUT this depends on the story and episode. If it's ongoing and a novel isn't updated as frequently, I prefer longer episodes (though I would REALLY prefer they split the long episode and post more often, because I have a terrible memory and forget what happens with too much time between). I also don't like randomly cut short episodes at the expense of the story. As long as your episodes don't drag (sometimes I find myself skimming longer episodes), longer is okay.
Do you schedule your posts or do you post when you can?
I always schedule, but I don't publish until I have a complete story that only needs editing or a very large buffer. That's a personal thing because I have a messy writing process. But regularity is important with a serial. It shows readers that if they get invested in your story, they'll have consistent updates and get to finish it. And it eliminates the stress of trying to remember to post or post on time when there are other things going on.
Oh, Edit ^^: If you're interested: