Thanks for playing, glad you got into the flow and had fun! It’s definitely easy to lose track of the subs. We tried to help with that by making the Sub and Upgrade buttons pulse when they are ready, and you can also leave the Sub panel open the entire time you play. Great catch on the 1000+ resource counter btw - we saw that overlap during playtest but ran out of time to patch it. We'll get it fixed in the next update :)