Age of Wonders is a well known 4X series set in a magical land.
Planetfall keeps most of the mechanics but shifts the theme from High fantasy to Soft Sci-Fi.

In general if you are a fan of Age of Wonders 3 you will most likely like Planetfall.
Additionally the price to content ratio of the Premium edition is fantastic, especially during a sale.
There's a lot of content added by the season pass, too much to reasonably talk about in a short review.