Okay, this might be a completely wacky, unworkable idea:
A matchmaking option for two random solo players to start a new game in the same world and server. There would be two Sacrificial Stones at which the players spawn, one located somewhere west and one east. Separate isles (maybe world creation would need to be slightly altered to accommodate for two "Meadows + Black Forest" starting isles).
Some necessary rules would have to be:
- A player cannot damage any structure that's within range of the other player's workshop or stonecutter. Also cannot build within 100 meters of these – unless both players agree for this setting to be turned off.
- Players cannot damage each other – unless both players agree to turn PvP damage on.
- Global chat is on only if both want it on.
- If players team up, enemies are scaled up in difficulty. In practice: if both players deal damage to the same enemies within a 100 meter radius, difficulty is scaled up for two players.
- Cannot use other player's portals unless both agree to turn the setting on.
- Probably a ton of other stuff I haven't thought about.
Basically, as a solo player, it would be cool to know there is one other viking in the world with me. Not more than one, so the world doesn't get too small. Finding signs of the other player's activity, finding their bases and other structures would be pretty cool. Running into them by chance would be cool, too. But you can still play the game completely normally as a solo even if the other player abandons the game.