Lord Parkin's suggestions got me thinking about completely symmetric arrangments of 6 players.
There's one quite interesting one based on the
projective plane, if only that was implemented as a map-wrap-around option.
Getting back to the reality of 3D space, there's still a fair few options. The circle or ring has been mentioned, it's not completely symmetric on a cylinder wraparound map (i.e. the normal option), as the players to the left and right have an ocean route to each other while the top and bottom players don't. This isn't probably such a big deal though.
There's also plenty of completely symmetric options that arrange the players like the pips on a dice, or like the white squares on a 2x6 checkerboard, where the land wraps around the whole planet. For instance a zigzag landmass like "/\/\/\/", or vertical strips connected across the middle "-|-|-|-", or just a flat band around the planet.
You can do some awesome things with toroidal maps. You can actually set it up so that each of the 15 pairs of two of the six players (and amazingly you could even still do it with 7 players) have a significant section of common border between their lands. You should even be able to get all pairs roughly an equal distance from each other (although I haven't confirmed this). EDIT: Here's a
wikipedia link explaining what I mean here. If each coloured region is a player (with the 7th an ocean maybe?) then they all share borders here. Not quite the same distance from each other pairwise, although a bit of manipulation of how difficult it is to travel in different directions could nearly make it so. Completely symmetric layout though which is nice, as well as great potential for conflict with everyone bordering everyone else.
Of course despite all this silliness, I'd be just as happy with a random fractal start - complete with asymmetric locations, risks of isolation, differing quality starts and everything else. People are probably going to whine that their start wasn't as good as everyone else's anyway, the more similar you make them the finer the details people will pick on. The more effort the map makers puts in evening things out the more justified people feel in blaming them for mistakes. At least if it's completely random people can complain about bad luck but can't direct it at anyone. In which case they should really just learn to suck it up and make the most of it. I much prefer the idea of everyone having completely different random starts and playing the map in different ways than all having the same land and doing the same things with it.
But that's likely just my minority opinion, and I'm happy to go with the flow.