I had an idea, and it might be incredibly stupid/hard to implement, but here goes.
Many people don't like the current crossroad system (Atleast in its current form sans travel weariness) but right now it's the only real way to trade. Now, how about being able to catch and tame say, pigeons or hawks and have them appear in your character menu. These animals would be very much limited compared to regular characters, both in terms of actions and stats, but would fill a specialist role and could be improved by breeding & increasing their quality.
Let's take pigeons for example. They're meant for scouting an area quickly or transporting small items across long distance. They move at sprint speed and ignore hitboxes/water and do not have an inventory but can be given one with a leather(2x2) or silk (3x3) bag. With the size of the new world, people would be able to travel relatively quickly to perform small trades at low risk (If someone kills you then you only lose the trade and your bird vs. your trade and a main/alt character).
There'd be a few other caveats; no study inventory, no hearthfire, no black skills (maybe have a raven with theft but very low health idunno) and also have time be limited by "pony power" that regenerates while logged off or faster if logged off in a chicken coop/kennel
With this system there could potentially be other things you can control too. Maybe cats/dogs, or even the nidbanes. That's all I've got for my suggestion, again it might be really dumb but I think it'd be a fun addition to the game.