We just completed the first mission :) It means that now it's possible to actually play missions. The next step is to create a mission control where you can choose which mission you want to complete. The basic idea there is that when you complete missions you'll move up in the ranks and more challenging missions are available.
We are now considering how many missions there should be in the first early access version. Naturally it directly affects the release schedule. What would you prefer? Our experience is that a single mission will take from 15 mins up to several hours to complete so there will be lot of gameplay hours even with fewer missions. And of course there's the sandbox mode where you can try different ideas.
Here is the first gameplay video. Feel free to drop comments here: https://www.youtube.com/watch?v=8eIbDprA4nc&t=21s