Map dimensions can pretty much be whatever you want, I'd ask that you keep them less than about 30,000 turfs each. They can be linked with gateway nodes, so it really shouldn't be necessary to make them too large. As I stated before about "regions" and "zones"... what might be a very large map should instead be a number of smaller "zones". There are ways of triggering gateways on and off. For instance, I have a magic school that is accessed by speaking a magic word, and then walking around a bend, when you come back around, you're in another spot. There are LOTS of things that can be done in the maps, but probably more than I can rant on about in one post, I'd prefer that people ask how something can be done, and then I can rant on that topic.

Thank you all for your help! I really could use it.