All the answers seem top be from people that bought a FC. So here is the perspective from someone who doesn't own a FC but has used them.
First I thought FC's will be useless and I would still say that a lot of things these are for can be done in different ways. But than again. We can go to Beagle Point with an unengineered ASP Scout.
The first time I was very happy that a FC was nearby was out in the black and hit a rock or something like that and my hull was down to 30 %. I still had to travel several thousand ligtyears and I don't caryy repair limpets. Before FC's I would just have continued. 30 % hull is plenty.
But at that time parts of the DSSA had been deployed already. And it turned out that CMDR Icetuuth and his (her?) Galactic Unity was just 40 jumps away (or so).
Beside the fact that I could repair my
Kassiopeia was I very surprised that I liked the (more or less imagined) social aspect of it. I never needed company on my travels before but after a couple of weeks out there, it actually is nice to see another living soul … because after a while my peduncle tree starts talking back to me but the conversarions are rather simple, like "Do you remember the M class star from a while back" or "don't you agree that the sound of this gas giant is very similar to the one we've scanned some time ago … you know, the one with the stripes" … (yes, that part was shamelessly copied from the original post in another thread

).
So here the FCs add in the form of the DSSA an important new element to the game. I think more commanders might want to try exploring into the far-far-away.
The DSSA could also be supported with a "shuttle" service. Several FCs that just go from one DSSA point to the next and in a rundtrip to the bubble, for explorers that got space madness and want to get home without using the Suicidewinder.
And yes, In my opinion that is proper exploring, too! Forget all the crap talk about "real explorers"! Just get out there!
The second time happened today. I'm doing missions to increase my standing with the factions in Colonia. Before I payed them, did passenger and data delivery missions and source and return missions. I don't do combat missions. That is just not the pilot I am. A while back I did mining missions but these take too much time.
But sometimes all missions a faction has are combat or mining missions. So I'm waiting and waiting for a "pay me 1 Million credits"-"mission" to increase my reputation with them just a tiny bit.
And here the FCs come now. The sell stuff that can be mined but is NOT sold at regular stations!
THAT IS AWESOME … and makes total sense! Finally a market for all these materials that float around in the belts.
So a FC is parked around at belts, miners carry (regular) material from the belt to the FC and a transporter carries them to the persons in need.
I know, if one JUST wants to make as much credits as possible that doesn't make sense. But for somebody that just wants to play for an hour, do some missions, feel like a space-trucker and than carry on with RL this is perfect
So long story short: FCs can contribute game elements that were lacking so far and that make total sense. BUT I admit that this may require some kind of "relaxed" perspective on the game … maybe some "role-play" as I wrote above in which a commander imagines to be a space pilot with a story (even if it is just a tiny bit in the back if her (or his) head … like me) and it doesn't work with the "I need end-game stuff now and complain afterwards that the game has no content" crowd … be honest, a game that has hundreds or thousands of hours of playtime is not really lacking content … even if the content comes from other players (DSSA, expeditions, BGS, etc. pp.) or from yourself (said own pilot story) and not from FDev, it is still content.