Why should a 6 ship alliance get a payout of 250% more than what one ship can bring in? Because there are six ships handing in loot. Could argue more hands make more money and this is one of the benefits of working together with people. Got to bare in mind that while it is Sea of Thieves that doesnt mean everyone plans to steal. Alliances were put in this game to give incentive for players working together as well as stealing. You could argue that the work of putting an alliance like that together is a fair price to pay for a large payout just as a pvper can sink one ship and gain 3 hours worth of their time in gold.
If they decide to list top money winners then yes that does become a "stat" advantage and it would need to be addressed at that time. Something I would need to think a little more on if im being honest.
I honestly don't see a balance issue at all. 16 pirates working together is always going to make more than 4 pirates looking to steal someones hard earned loot. If pvp players can make big sums of cash and do no work for it (other than sinking the ship) why should alliance players not be able to reap a benefit also? I think its fair enough as it is.
When it comes to stats though you are right. I think perhaps we should have tracking for pvp stats and I will admit I think that SoT needs to recognize their pvp players more than what they do currently. And I genuinely believe they will do so.
Running severs days at a time is a bit of a stretch. I have heard (so I cannot confirm personally) from people I have sailed with in the past they have had servers give them a notification they are shutting down in ten mins. Iv seen server health go real bad after extended periods of time. Really big lag spikes, stuttering, rendering issues and its not a case of iv played to long in the session. People join and right away boom, server is potato. So days at a time is a rare occasion id wager, but yes it probably does happen. I do however think its fine. If people are going to invest that much effort into it why shouldn't they get a good payout for it? Takes a lot of work to keep something like that running.
We are talking about balance yet I don't see any issues with the balance. Solo player getting 350% would be a huge advantage. But 16 people getting tons of cash for lumping in together and banging out voyages. They do the work they get paid.
If pvp ships can make money quickly and in big amounts and not do the work, why shouldn't pve players be able to lump together, work together and benefit?
Thats my take.
I will also end here by throwing in my own play style here, thought it might add in some context.
I tend to gravitate towards PVP in SoT but I also do a lot of pve as im a completionist. But pvp is where my fun comes in. I have done my fair share of alliance breaking. Mega keg on an alliance ship and watching them all blame each other is some of the best fun I will ever have in this game.
But I also do love the pve and being able to team with other people and have a good ole laugh.
Great thing with this game as it can go both ways and often to the far extreme. Casual pve, casual pvp, then theres lets go die hard pve or lets sink everything with a sail on it. There is something for everyone.