Ok, here are a few tid bits of feedback on this,
First, the Indoor section is much too dark, and I would heavily suggest opening it up to the outdoors a bit. This could be Windows or little sections that are outside which are connected. Anything Which can really light the place up.
Secondly, The outside displacements are unnecessary for Alpha one. You can either keep it flat, or make some height variation which you can smooth later to make really good looking displacements.
Thirdly, the map is quite 'oversized,' which means its all larger than it should be. you can usually stop this by either placing hwm models down, or following the 64, 256 rule. you can find good tutorials in the tutorial forums, which I'd suggest checking out.
Overall, its a nice attempt, and I urge you to keep mapping! Welcome to the community