So if a separate sandbox mode would to be scrapped, would ship designing/testing jobs be acceptable solution? Ie. factions would offer the resources to design and test the ships, and there would be areas/stations dedicated to ship design/testing. I always imagined I'd be building the Empire this way, and there would be great need for a lot of ship designers (and not just warships, all public transport, mining etc. ships also need designers), and the large design/test ranges and factories inside the game world would indeed add up a lot to the universe. But if we would be to scrap or at least postpone sandbox that might guarantee the labor needed for massive progress ...
This is the kind of solution that keeps players in the game, working together. We lose this possibility if everyone escapes out of the game to design ships. I'd much rather see people doing test flights in live around a faction station, crashing into things sometimes and so on, having to apologize for hitting some other ship, helping them repair up, than everyone having perfected their flight offline and everyone thinks they themselves are bad at the game the first time they try to build a ship and it doesn't work out how they expected. Basically, seeing other people mess up helps you realize you're allowed to mess up too.
I imagine Empire and Kingdom could offer jobs for ship building, and also offer access to resources. This means a ship builder wanting to get ahead in the world might offer their services to a faction; it incentivizes players to join a faction and to remain a part of it for a while, at least until they finish their job of creating the ship for example. This also means Empire and Kingdom can incentivize technological progress - if the pay attracts a lot of ship designers, then they will be working together to hash out the best solutions to problems. With a lot of people, with access to resources, working to make the dev factions stronger, the dev factions will have the best tech in the game. An arms race and a technological war develops immediately. This might eliminate any form of offline ship designing and even allows for piece-by-piece designing of ships in the live game (as in... always). Even though ship designing might be complex, having to do it online, frame piece by frame piece, leads to massive shipyards full of parts and activity and ideas. You'll see shapes and ideas and incorporate things into your own designs and have a lot of people around you doing the same thing to ask for help from and so on. This means production factories which piece together ships start to be a thing; the best designs, players will want everyone to have that good fighter ship, and now you have people working on manufacturing plants and the best way to 'factorio' all the resources into parts, and parts into ships. This amount of gameplay is a nuclear explosion of possibility. Only possible if the networking tech (and frame rate) allows it.
The downside to this is it might be a massive undertaking to manage this, and would require a lot of time on the devs part, but that might be good as you'll have to play your own game more. It could also be bad, as you get influenced by people who suggest game changes due to quality of life concerns they have which might actually be good for the game (difficulty is good). The upsides are very large however, as you develop ship design teams, have jobs for resource collection and transportation, and so on, incentivizing players to do things, they all interact and you get an explosion of activity around shared goals. As things get complex, you will have to delegate responsibility and so on and people will push hard to achieve 'ranking' or whatever. This can be dangerous, so perhaps you have to set a term of service that expires and the players get kicked from the faction. This is all super complex, wishy stuff that has no programming systems required behind it. It's like managing a mega-guild in an MMO, so it has great upsides and downsides. Some of the upside includes the presence of sabotage, thievery and so on; natural drama that would occur. Sometimes this can be negative, as people take others' parts and so on (secured, group only building bay perhaps?). People accepting a job to transport resources who then just head off into the void of space, never to be seen again. I am unsure how this could be managed. It's massive. Maybe I am over thinking it and you will just have people produce some flyable ship as a job and they get paid and you get the blueprint as a faction blueprint, and if it is good it gets used and if its no good no one uses it.
The gameplay that can stem from this is immense and that excites me. This also solves somewhat of a problem with MMOs with dev factions where people often just spread out and the dev factions are small and ineffective - if the resources, best tech and convenience to build are focused somewhere, people will gravitate to those locations. Future pirates will have learned to fly in the Empire or Kingdom ranks. They'll have stories of their military career. It kind of becomes an online sandbox for a ship designer - why waste time mining all your own resources when you can join the Empire for a while and build to your heart's content and learn all the game systems cheaply? It's like having online cheat mode for access to resources and things to shoot at, except in doing so there's a crazy amount of gameplay generated as everyone seeks these same conveniences. Likewise, knowing there's expensive ships and sometimes inexperienced pilots, this draws a lot of pirating and gives natural gameplay through supply and demand. I would just mention again how difficult this is to manage, because too much resource and you have inflation and no one valuing the resources, so if at all possible, having a large stockpile of resources that deplete, where resource gathering jobs are required to replenish a stockpile; you'd be able to offer no pay for ship designing for a while and only on resource gathering and direct gameplay through in-game means.
I could be way off in how you're thinking this would occur. Maybe it's just 'create a flyable ship blueprint in this testing environment where resources here never reach the outside real game world' - like a large test arena in the middle of a station. Not sure how that would work. So it could be as simple or complex as you envision, but keeping all that action available for people to see would incentivize cooperation and make players invest into the success of the faction. Just don't let all that dev power go to your head and artificially alter the outcome of events in the game!
Lastly I'd have to point out again the main topic; none of this matters if there's a single offline server to accomplish any of this in. If a player spins up their own 'Empire' in their own private server, it devalues the one and only Empire that would otherwise exist in the live game. Games in the past have had to do this, because networking 100's of players together one one server was impossible. SpatialOS developed and showed even then, with multiple servers handling interactions, it can still be problematic. You guys have developed tech that turns every player into a server, and this seems like an obvious solution that every MMO game will incorporate one way or another in the future. This means we might get 100's of players together in one location, all processing all their own actions, and just telling everyone else around them what happened. It might work. As such, you have the opportunity no one else really had, to bring together players in a large universe like this. EVE used time-dilation; a single server just processing every action in sequence no matter how many actions were occurring, and it worked overall. So if the tech can support it, it would be a great loss of potential if there was ever a 0/32 player Starbase server out there. You guys controlling the tech seems much more valuable in crafting the future of the game and making it something unique; gameplay you cannot get anywhere else, not on StarCitizen, not on Elite, not on Space Engineers, nowhere else. Only in Starbase, online, in this one game universe, can you experience this gameplay. That seems so powerful and exciting. Again... if the tech allows it. If you can pull it off. If instead, like Worlds Adrift, it just cannot handle the numbers... we're back to square one. But I have a feeling this works, which is why I'm pouring a lot of attention into Starbase. I see it.