With my usual metric of game enjoyment - hours of interesting playtime divided by price in $ - Star Citizen actually does rather well, for a $45 entry it's definitely generated way more hours of actual fun with friends than most $60+ games we've bought.
It's definitely also generated lots of frustrating hours, but that's rang true for said $60+ games as well. I really wish there were more other games which do some of what it attempts.
ED was fun, but me and every one of my friends who're into space stuff have all individually burnt out on that game due to the frankly insulting level of grind.
NMS turns out to simply not be the gameplay we're after, so I have even less playtime in that than ED.
So far, Space Engineers and Avorion have been doing the best in that regard, still hosting a 24/7 Avorion galaxy for us in fact.
X4 has been collecting plenty of hours of playtime for me as well, but it's lack of any kind of meaningful multiplayer with friends does lessen the enjoyment somewhat.
Space Engineers has a bit of a learning curve, but it's definitely a nice sandbox-style game, just unfortunately a bit lacking in PvE content without mods.
Avorion on the other hand is much easier to get started with, but it's also quite shallow in regards to story and such. The galaxy it generates can definitely be interesting though, it has a remarkably robust system for reputation, organizations, etc - and it applies between NPC factions as well.
I can personally also recommend Stationeers if you're a fan of physics (in this case temperature/pressure/gas instead of movement) sandboxes, it has an even steeper learning curve than Space Engineers though, but it can also be loads of fun.
Have you checked out Starbase? It may be considered "dead" nowadays (I myself haven't played in a little over a year), but it's like what Star Citizen wants to be. It's an MMO in a MASSIVE shared server with everyone. You get to literally build your ships from scratch (and decide where literally everything goes, down to the bolt placement), or you can buy pre- and player-deisgned ships. The game takes place orbiting a gas giant with like 7 moons and a huge asteroid belt, except pretty much everything is actually to real life scale. It's ENORMOUS, but so cool.
Yep, played Starbase for a while, the lack of any meaningful PvE or 'survival' content ultimately killed all my interest in it even while it still had some support. Construction for constructions sake is just not something that vibes with me.
Their construction system did remind me of hosting Spacebuild and ACF servers back in the good old Garry's Mod days though, making all manner of wiremod vehicles on there.
I'm personally waiting and seeing what Starship EVO is going to do in regards to PvE/survival/crafting, since it might be a really nice Space Engineers contender if they do it well.