If you (or other commenters) are interested - habitRPG does a similar thing with points for tasks + points for rewards. It's a website, and it's primarily designed for habit forming, but i've used it to get on with annoying task lists
I like habitRPG! I used to use the website and now I have the app.
I don’t personally find it intuitive for making changing daily lists of new tasks; it’s not customizable enough for the way I use my point system, and I don’t like it that non-repeating tasks disappear after you do them (rather than staying around crossed off as a trophy of my victory).
However, I do find it really useful for repeating daily tasks and habits! I use it for stuff like washing my dishes and making my bed and meditating - stuff I feel better if I do every day, but that’s it’s really easy for me to just stop doing and fall apart on. It’s very helpful in that respect!
Seconding the recommendation for other people!