I have been looking for a game exactly like Planet Explorers for years now. Essentially, I wanted a game about exploration and building, with an additional leadership/colony establistment dynamic added. I always played minecraft near villages, but the lack of content aimed at interacting with and leading the npcs always left me disappointed, and I wanted something better.
In Planet Explorers, you crashland on the planet Maria after something happened to the space ship, called the Epiphany, carrying hundreds of colonists. Your early quests involve providing immediate assistance and reconnaissance to the scattered and lost crews, who came down on different "lifeboats," crashing their smaller spaceships all over the main continent.
Maria is a very beautiful, engaging, and dangerous world, and I feel that I have only scratched the surface in the hours I've spent playing this game. There are different regions, called biomes because of their differing ecology, where different herbs and resources can be gathered. I find the game challenging, as early in the game you start of with very little and you can't craft everything all at once (in story mode, there are other gamemodes for just building or adventuring without the story constraints). Mining is more challenging than other similar games, because mining to a specific level isn't the answer. You use a scanning device to find various minerals, and their distribution is fairly unpredictable. Building is well done in this game, because the block is visible before it is placed, so you can get it positioned just right then place it. You can also place partial blocks, which adds detail and customization potential. Removing blocks is as simple as pressing Alt while in buildmode. I haven't built much so I'm not sure how complex what you can make is, but so far I've been pleased with the mechanics of it.
Another fun thing about this game is the createable content. Swords, guns, vehicles, and even decorative items can be created in a special interface, then once you gather the materials to make the item you can simply export them into your game. So far I only have a vehicle in the car category, but you can make everything from motorcycles to fighter jets. If you are lazy like I am, you can just go to special websites to download the "iso" files, which can then be plopped directly into the files for the game. So far this has been the route I've taken, because although thorough and very customizable, the creator tool seems tedious to me.
I just reached the point of actually establishing my colony, and I have been pleased with the mechanics and purpose it serves. I won't go into it much for fear of spoilers, but it is very customizable and there is a definate leadership element to managing the colony, it isn't a passive structure but an active community. It is also important to point out that this game is in Alpha presently- yet I am more excited and impressed with this game than I have been with many fully released pc games on stream. I definitely recommend this game to anyone looking for a challenging, creative, beautiful game about space exploration (gone horribly wrong- in a good way!).