I gave Spacebase DF9 on the weekend. As an alpha game the learning curve is pretty steep with any mistakes being punished with death and failure.
The summary of the game is Dwarf Fortress in space. You are creating a spacebase but really it is the occupants of the spacebase and their lives that is of interest.
At the moment the game's difficulty is sufficiently compelling that with each failure you feel like you've made a bit more progress and understand what you have to do a bit better than you did before.
At other times though the alpha-ness sticks through and the base starts failing because you can't intuit what the interplay within the systems is. If you don't grow food, people starve, if you grow food then you also need a pub to turn it into meals. Do people want food or sleep more?
The construction tools are also opaque with objects having a minimum room-size radius but no apart problem with being placed next to one another. Some objects require a wall to attach to but there is no feedback except the "can't build here" red.