I've been thinking about some form of parlay in this game for years and now I have a bit more knowledge about game development I think I have a viable suggestion for how to do it without compromising the core gameplay.
So, I am thinking that if Parlay was a kind of global new reputation tied to all trading companies, almost like the outposts having their own rep system. I reckon it could work like this...
When on the same outpost as another crew, all crew members in close proximity of each other would gain levels in Parlay passively for not killing each other, up to a maximum. This could benefit from using a variety of emotes (with a short cooldown to avoid spamming), drinking grog together, forming and holding Alliances, etc.
Once out at sea and far enough away from an outpost, your reputation would decay slowly. The decay would be even slower if in an alliance and sailing within a certain distance of each other. The greater the level of Parlay, the slower the decay will be when on the seas completing voyages. In the event that someone gets killed by another at the outpost, thus breaking the parlay, the offending side's Parlay rep will immediately begin to decay at a slightly faster rate than normal for a limited amount of time.
Based on the level of Parlay, there's a marginal to great bonus to overall trading company reputation gain because they see you as honourable pirates who respect the code.
I feel this system would work because it has the incentive of easing reputation grinds and enables more friendly interactions at outposts to make them feel more lively and less intimidating to dock at if someone is already there. Should help facilitate roleplay too. Lastly since it's opt-in, it doesn't deny players their right to be aggressive but rewards them if they aren't.
So yeah, throw in some nice commendations on top of it and I think it'll enrich the High Seas experience for everyone. I also think that thematically it does make sense too.
Not sure if it should have an effect or be affected by Hourglass factions but Rare are smarter than me so I'll leave that one to them.

