How's it stack up against (for example) Rogue Trader? Interesting companions, cool stories, wide variety of build options? Is it feasible to run a character who makes combat manageable not by being an enemy destroying combat monster but by doing stuff outside of combat (like making sure the group is far ahead in terms of equipment or by allowing you to pick and choose which battles you fight and under what kind of circumstances or stuff like that)? Or is it more of a tactics game with RPG elements like the old school RPGs (Golden Box and that kinda stuff)?

This is a solo-dev indie crpg, so in terms of basically everything it doesn't stack up against Rogue Trader, but that's not a knock against the game at all. It's just that Owlcat has 10000000000x the budget and employees compared to this game.

For this game, Sector Uknown, you definitely have the freedom to build your characters and parties out however you want. You also have the freedom to go around attacking ships in orbit, or not. You can solve issues on the ground by passing certain character build checks, or even if you do pass them, choose not to and go into combat. The game gives you a LOT of freedom.

I'm still only on the second planet, and there's a TON of quests. I'm still adding members to my party, and unlocking things in my home base as I go.

So to answer your question: it's more a standard scifi classic rpg, and definitely not a tactics game. (I generally don't like tactics games).