The UI interactions look great. I specially like the completion pie chart on each project, great idea.
For the non-Apple people, I've been using Todoist, and it has been pretty great. It is polished, and well featured, and it has some pretty cool features (loving the karma indicators every day). They've been around for 10 years and (even if you never know) they are in this
for the long run (looking at you wunderlist...) and they are remote, bootstrapped and profitable.
I don't think it is that expensive though, a couple of years of todoist premium are 60$, which accounts for desktop and phone Things. So if you get a half-life of 2 years it is around 2.5$ per month which is pennies if it is a useful tool for you.
Happy todoing!