Hi. I wonder if you have checked out WikiWand, which does something very similar to Winter. It could be interesting to see what features they've implemented and how relevant they could be to Winter.
What's interesting is that the website claims to increase Wikipedia load speed by 3 times, which is astonishingly fast. I wonder if the Winter team could look into what makes Wikiwand faster, and maybe implement something along similar lines to increase speed as well.