Thanks you all for your comments.
Very nice map RunDrag! I can see that you have focused also on the inner city transport. Is the dense area in the south-east 1 city or did you put together few cities?
This urban area is compose of four cities, that has grown together into one big metropolis. I experimentally set up the inner city transportation on the chessboard system, where horizontal train lines are squaring with a vertical bus lines.
The map is really good. Didn't looked it so deep. My PC can't handle it.
And the number of vehicles is scary.

I tried to load it on my old laptop (1.5 GHz Pentium M, 256 MB RAM) and it can handle this save relatively good.
Nice island too! Do you perhaps have a heightmap as well?
I have the heiqhtfield map, but the source is not my. I just addopted it for Simutrans. So I am not sure about uploading it.