Everyone who played and loved "The Settler 2" should give this a try. It has even more depth and removed a lot of the quirks like managing the stationing of trained soldiers.
How mature is the game? Can it be recommended to players looking for a complete experience or are there still many bugs and obviously unfinished features?
I would definitely recommend to try it out right now. I‘ve never encountered any bugs and it is very polished overall. I think the only things that are unfinished are some story campaign scenarios, but there are enough in different difficulties to keep you busy for quite some time.