This is pretty good. It's missing the "WOW" factor though. I see you've worked hard on this, and you did a good job with what you built, but a few things feel out of place... It's missing a theme, and it generally just needs spiced up a bit.
If you spent some more time on it and really tried to perfect it, it could be a great map! You just need to spice it up. I feel like there is a lot of empty space with nothing in it. You don't even need to build things, just use a little nearby cave, add a trap or two, and it already feels a lot less bare.
Also, while the structures look nice, they also look... stale. It's not one of those things like "wow, looks nice, haven't seen anything like that before." It's more like "Hmm, a pyramid... Looks a lot like pyramids I've seen before... Nothing special." You have to add a bit of flavor to it. Right now, the little castle area, the pyramid, and the igloos all look like something you would see many times all over the place in Minecraft. You need to add something to it that makes it your own, something that makes it different.
As well, with a theme, you won't be getting people who like half of it and hate half of it. I love myself huge mountains and jungles like are in map three, but if all of a sudden I come across... A plains biome and it's just empty flat land... I won't like it. I will still like the map, but in order to enjoy playing the games the most I have to limit myself to where I want to go rather than where I have to go. You have to have some sort of theme so people can have both.
TL;DR: It's not bad, but it needs some work. With some work, it could be great!