[HEYGRANDMA]

Kerbal Space Program is fantastic, I'll always recommend that. It might be worth checking out Gnomoria too; it's a lot easier to get started with (IMO) than Dwarf Fortress, but still provides a lot of mechanical depth.

[rurounijones]

I thought it was abandoned by dev's in a buggy alpha'ish state

[HEYGRANDMA]

I think you might be thinking of 'Spacebase DF-9' by Doublefine, which was released in a fairly primitive state and then basically never updated.

Gnomoria is already quite advanced (mechanically) and has been getting content updates for ages.