*Good Sauce's infinite river seems to be a common feature. Most of the maps I looked at had a single river running in a straight line across the top of the map. This then branched off and meandered its way down into the central, inter-sea region, where it met up with a long straight river across the middle of the map. A few tributaries then branched off from this into the southern regions.
I figure this is to allow trading between civs without having to wait half the game for road connections. It does mean, though, that we're likely to be dependent upon having OB with civs in the central region to maintain trade connections to those in the north.
*There's a hell of a lot of land - by my estimates, about as much as on a Large Continents map - and some starts are very isolated. If we do find ourselves stuck out on our own, then those Impis are going to spend their time killing barbs (and the GW will be a no-brainer). If, on the other hand, we start out with neighbours close by (and we kill them), then we're likely to face some incredibly massive rivals later on.
*Seafood is extremely rare (like one fish and one crab for the whole map). Other health resources are abundant, though, so

shouldn't be too much of a problem.
*There is
very little tundra - never more than 3 or 4 tiles deep at the poles, usually only 1 or 0. The fact this start has any at all means we're very close to the bottom of the map (close enough that the capital's fat cross will bump up against it sooner or later), so we'll almost certainly want to move the capital, perhaps even fairly early on.
*On most maps, the best land looks to be in the central region, where deserts are largely absent and rivers are abundant. There's a band of jungle here too, but it's patchy and very thin. Elsewhere, the land is pockmarked with many large patches of desert.