I'm glad you liked it and congrats on finishing the last deadline!
I agree with much of your critiques. If I had more time I would do a better job of providing clarity to the user on things such as project progression and what colors the categories go along with. Thinking back now, I could have easily included that right on the projects themselves... oops.
I think an endless mode could be fun, but I decided against it for this project in its current state because I think that with more time, I could build a deeper game with more strategy. I think once people reach day 50, they could just blow through anytime else. But yeah, endless mode would be great and it's how this kind of game should go, unless you carry your cards into another level.