Let's consider No Man's Sky. NMS gives (as in literally gives) each player a fleet carrier freighter. I personally think this is the "too easy" mode that Babelfish worries about. However, if FCs were like the NMS freighter before the Oprah Update, where you had to really earn them (they cost a lot), then I think NMS serves as a good model for how solo players can use freighters with an NPC crew. I'm not talking so much about the minute logistics, but rather the big picture of purpose and management.
Taking this back to ED, I suspect "unlocking" a fleet carrier will be a wing mission, as this is the best mechanic in the game for group activity. Thankfully wing missions in ED can also be done by Solo pilots (they were designed this way on purpose), albeit being a much greater undertaking. Repairing a FC (which I imagine can be attacked just like megaships) probably will parallel repairing stations, though hopefully at way less 'cost', which will give true Squadrons an advantage over Solo players owning FCs. In other words, I cannot imagine it being 'easy' for a Solo player to acquire and maintain a fleet carrier, but hopefully it's not impossible, either.