Designing playable locations

In Fallout designing playable locations is a bit different that let's say designing castles or dungeons in Neverwinter Nights 2. Even with fantasy settings that have "long lost civilizations or ruins" have a different feeling to them than Fallout setting locations.

In my opinion you have to first not to think about the adventure player is going to have. Well, not completely true since when you think of a location you have an idea how it fits into your story or quest. But point I'm trying to make is that first you should design the area as it was originally planned for: a shopping center, a gas station, a library or a powerplant. Put in place buildings, roads, parking areas, bus stops, houses etc... all the things that are needed there in real world. Think: Why did this area exist in the first place?

Then break your area, destroy it, nuke it! Imagine what the place would appear like after nuclear holocaust or 100 years of non-activity. Is there power? Is there ruins? Are there cars? Has the river water flow stopped? Make your area show the contrast of what was and what is.

Finally make it fun: have raiders built a base into the area? Has someone moved all the rubble and scrap to make a fortress? Have mutants spawned into the area? Is there still some unlooted treasure? Can you find desperately needed resources there? Can I charm the enemy to attack it's allies? Are there still some 100-200 year old robotic defenses active? Oh, and add multiple ways to "win" the area: fighting, negotiating, hacking, lockpicking or just exploring diligently. Personally, I think shooting and fighting are always the option for retarded players and should (and will in my mod)) always give less XP and less adventure than any other approach. However, this is Fallout and some ultra-violence with black humor is a must. But only when used rarely. Of course if someone likes to roleplay a mass-murderer, go ahead, but I find it boring.

So, anyway: build, break & fun. That's my "design method" :-)