@fassgatto
What this leads back to is cosmetics, an increased pay out for loot sold in exchange for gold at grade 5 Emmisary is supposed to be the incentive, the problem is with the lack of diversity in types of things to earn / purchase.
We have an abundance of these cosmetics:
Pirates: titles, hairstyles, tattoos, scars, curses, beards, hats, eye patches, coats, shirts, gloves, hooks, trousers, boots, peg legs, finger rings, dresses, costumes and skirts.
Weapons: cutlass, flintlock, blunderbuss, eye of reach, double flintlock pistol, blow pipe, harpoon gun and throwing knives.
Ships: top flags, sails, hull, figurehead, capstan, helm wheel, curtains, chandelier, table, chair, carpet, trinkets.
Players that have been around for awhile have a maxed out fleet with their ships decorated as they want them to be and many many combinations of pirate cosmetics making up everything they could ever want from these selections, new items in these categories maybe no longer matter to them so much, so the only thing they spend gold on is supplies. Players that haven't been around for a long time may only want selected items from these that suit their tastes. A minority of collectors and commendation hunters will be seeking to obtain everything.
Possible solution:
New cosmetic types such as jewellery at ultra prices. Wouldn't be a permanent solution but it would help with some engagement for awhile with the purpose of earning gold to buy cosmetics with and the best way to earn gold is by being a grade 5 Emmisary.
And... New faction (s) with new rewards.
Looking at SOT from a new player perspective, I imagine the amount you can do and get would be quite overwhelming so I imagine the tendency is to be selective about what to go after rather than trying to obtain everything. Veteran players on the other hand either don't care about what they don't have because they have everything they want already (some of which is unobtainable and rare now) or they have been collecting everything from the start and have everything so far, more or less.
You can't please everyone, introducing new cosmetic types and new factions would provide more diversity and variation and it would increase the amount of content, possibly making newer players even more selective about what they go after and veteran collector players may feel exhausted at the prospect that there is even more to go after if they are going after absolutely everything. Also, there are players that I think just like to horde gold so they may not spend it for anything.
Increasing distinction levels for the already existing factions and having more of the same categories / types of comsetics as rewards for those factions isn't in my opinion going to solve the problem of getting new or veteran players to engage more with the game or with factions.
Another possible solution may be to create a situation where players must choose who to represent and work for which has a visible impact on something in the game like what happened with Golden Sands becoming Port Merrick.