You'll want to consider the topography of your land and what direction the front of land faces when looking at a piece of land, especially if you're going to build on it.
For example, if you intend to build a house on the property and part of the topography of the land includes a hill, the house will be very well-aired a lot of the time if it is built on top of this hill, facing the direction where the most prevalent winds come from. Another example is that a lot of people like their bedroom on the north or south side of the house so the sun doesn't come directly into the room.
You should also consider the size of the land and how it relates to the house you want to build and if you want any other buildings on the property. Make sure you'll have plenty of room away from your neighbors - if you prefer that - and that the land is also big enough for any activities you'll want to partake in - anything from croquet to volleyball to practicing your golf swing.
When purchasing a block of land, it is important to find out what the situation is with the neighboring blocks of land. It is very useful to obtain information about who owns these blocks of land and if there any plans to develop them in the near future, as this potentially have an impact on your lifestyle and how much you can enjoy your own land. If you buy a piece of land with a spectacular view of a mountain, an ocean or a forest and someone builds between you and that natural beauty, you won't enjoy your property nearly as much.