I am mostly against alliance servers because I feel that it stifles creativity and the creation of any kind of economy or challenging content from Rare. I really have no issue with people wanting to play without threat of PVP, but I do think that it should be less rewarding to do so.
Why create more difficult or engaging content if it will just continue to reward gold which you can get easily from elsewhere? Balancing gold this late in the game would be a challenge, so I think it would be fine if Rare decided to reset everyone's doubloons instead (maybe give some ancient coins to everyone + some extra for people above a certain # of doubloons for people with obscene amounts like myself), and then decided to make those the new official "challenging to earn" currency which doesn't split between alliances anymore.
Doubloons could then become the "influence" currency, used to alter the game world in some way, change your ships attributes in some way to customize them, or buy challenging voyages which you can actually fail and which reward "coupons" to the emporium or doubloon store to buy certain cosmetics at a slight discount, or unlock the ability to buy others which are more rare. They tried a doubloon type economy a while back with the black market, but the prices were too low for some and too high for others. Only a full reset and making doubloons scarce / locked behind challenging content would have allowed this to work.
Nobody is going to do more challenging content or content which has more risk if you can safely do it elsewhere and earn the same boring old gold. So why would / should devs develop that content? FoF is competitive only for people who really need the athena rep. Otherwise, the gold isn't worth the risk for many people, and so it is losing popularity. And even if the majority of people don't participate in alliance servers, the fact is that outliers can doom an economy.
Take my example about repurposing doubloons into a bit more of an "influential" currency. I currently have close to 50,000 doubloons, and I know I am not even close to what some other people probably have though for others 50k might seem like a lot. But I earned those during a time where it was much easier to get them, and only did so because I thought that one day, they would finally wake up and do something meaningful with them. I actively worked toward them, got crews together to farm them, and had a blast earning something I thought would one day pay off.
Even so, my hopes for Rare doing anything with them are now nearly gone, and so I believe that they should reset them for everyone and reward people in some way for their time in earning them with a trivial amount of ancient coins.
From there, Rare should build the new economy on doubloons, leaving gold alone or maybe slightly nerfing the number of allowable alliance members, but making doubloons not split between alliance members.
I agree that any change to alliances would probably help the game. Maybe alliances work the way they do now for the first 2 members, but any new crews cause the gold to split. Or, require that crews turn in together at the very least so you can't optimally farm every event while running a bunch of voyages in a big alliance.
To clarify: I think forming alliances in the game is a good thing, and lets players like myself ally with new players, and help them turn in without feeling like I'm just giving away money with no reward. However, alliances really shouldn't extend to the whole server. 2 to 3 ships per alliance is about right. Alliances can then informally agree to a "non-aggression pact" but that tension will always be there.
Maybe another alternative would be to have "alliance queued" servers where you queue in with two ships which are automatically allied and split all treasure, and cannot ally with any other ships. Think that would be the best of both worlds, offering big groups a way to consistently queue in together without making it too profitable. Maybe options would be gally + sloop or brig + brig. If a ship has to leave, they can "open" crew and get a replacement ship, but this would obviously be less ideal.