Empyrion Galactic Survival is superior to Space Engineers as there is so much more to do and gets regular updates. It is still in alpha, but gets fixes and added content very often. None of the glitches are game breaking or frustrating, but there are some you will most likely encounter. Also lacks optimization so you might experience FPS drops, but adjusting settings can fix this for a better experience.
Has in depth crafting where you can build planet side bases, outposts and vehicles. For space, you can build small vessels, capital vessels, space stations and bases. The game is primary survival and resource management heavy, meaning you will need lots of different resources to build. They do have items to help you as you progess, such as autominers for planets and asteroids where you set it up and come back later to collect resources.
The game has Workshop support so you can download various blueprints to create things or you can create from scratch to make your own blueprints.
The game has RPG elements in character progression when you level up, you can spend points to create better items, tools, equipment, weapons, etc.
Lots of various alien life, animals, dinosaurs, plant monsterand more, some are predators while others will leave you alone. There are also hostile alien races, robots and monsters that you can encounter.
Exploration and raiding is fun, there's a lot of cool loot to find in abandoned bases, crashed starships or occupied settlements and bases. From epic weapons to rare resources, there's a nice variety of goodies in the game. Trading posts allow you to buy and sell goods.
Game looks good graphically and has a variety of different environments on the planets. Some are more difficult for survival. The game also has day/night cycles.
Game play is good, not great but works fine once you get the hang of it. It's on the list of things to get more polished in the future. You have first person and third person views, which are easy to switch on game. Menus are fairly easy to navigate and UI is decent.
Does have a bit of a learning curve to the game. There is a tutorial that you can do that will teach you the basics and the forums/reddit have a great community that will help. Has different modes (survial, craft, etc) to help with difficulty. Can be played single player privately or on a server and also has multi player.
This game offers a lot of content in its current state and overall is a enjoyable experience with minimal frustrations. I love the sci fi sandbox survival games and have played most of them. I feel it's definitely one of the best in its genre and does a lot of things right.
You might also be interested in No Man's Sky. With the newest update, Atlas, the game is very complete and super fun. Similar to Empyrion but with different focuses and a lot more polished. Despite popular opinion, this game is a blast and has come very far since release.