So i generated some maps to show what issues sometimes arise that need human checking or human start position placement. Also some features that I find really nice/cool, and some variety.
1st map would be really awesome with that bay at top right and all and second continent to race to, however that land "bridge", which would let triremes reach second continent really breaks balance, cause player(s) starting close to it will have huge advantage on expansion.
2. Basically similar situation with different arrangement
3. Map that looks to almost be made of two copy pasted parts, used low land content (15%), overall seems quite interesting and balanced with right player distribution (obviously by human)
4, 5 Maps generated "abusing" certain feature of fractal generation - setting place each player in separate continent, makes generator generate smaller "features" landmasses. But if you get even something like 10 players with that setting you might end up with total mess of tiny stuff. But it is nice to use 2-5 players to get nice archipelago type map with smallish continents/islands, but still of comfortably hefty size. Someone just needs to put some start locations in somewhat balanced positions, and of course disregard the number of players that was used to generate map.
6. Now that map just looks awesome/kick ass! Look at those two bays and imagine naval battles going on there!, especially the right one having such a narrow exit. I just love such narrow passes, somehow I think they are of big strategic value, cause in reality they are, to be fair not sure how such things translate into civ games. Also has nice mini archipelago near the continent. Probably did not varrant zoom in still, made it
7. Again nice bay bocked with island, thus having two exits from the bay, continents also divide global ocean into north and south having only two small passes between them. Look at this, isn't it pretty?
8. Again similar situation, only this time it also has this make your own passage zone:) at least two cities need to be placed on right squares to connect north and south. Wouldn't you fight for such spots?
9. Has do yourself an exit of this lake/bay kinda situation, with multiple location for exits. Also three continents, two larger possibly suitable for initial placement of players and smaller rounder "island" for colonization fights.
"End notes". Maps were generate in freeciv 2.3, not that it matters much really (though generator might be tweaked, also ruleset can have effect on how map will look, all else being equal). All these maps are rather big, 50k tiles. Thats one issue with such random generation, though I'd say certain minimum size is needed even for different generators(and scenarios), as otherwise its hard to get much "appreaciatable detail". That said I'd think maps even from something like 30k should have enough of everything, and should be fillable comfortably with current community size. (water content can help fine tune landmass). Sometimes I just so impressed with generated maps, features like mentioned seem to be really interesting, and there are quite a bit more possible variety.
Minor side note, I find default "number of hills" a bit too large as in some places wast areas are just hills/mountains, I did not adjust that here, as its not important for shoreline, but when generating map for game I think that should be adjusted too.