Well, I've only played 2 maps so far but I certainly like Mountain Pass more than Tarth.
Tarth is, of course very resource poor. I'm sure this is intentional and there is nothing wrong with having harder maps. At the same time, however, a map that has so few resources that you feel like it's hard to even get up and running isn't necessarily the most fun. I mean it COULD be, if one is already super good at the game and all.
I hope that the random map generator will have some sliders or drop boxes where the player can choose some of the parameters of the map such as land/water ratio, resource abundance, number of minor factions, etc.