I fled Wattpad a month after I joined Tapas, so you are not alone. In fact there are a lot of Wattpad Refugees here too!
The 15,000 character limit was definitely an adjustment for me since I had to split up my Chapters a lot. Yet it also helped keep my story flowing. Also Tapas does not have as many features that Wattpad has for uploading a story (like adding images is super not intuitive). Despite that however, I really like the people here on Tapas and I also like how things are laid out with my story here more so than Wattpad which was...messy.
I think you're in much better hands here.