Mapping advice?

[Adny]

I would advise against using a lot of different building sets in one area, it generally doesn't look good. I'd suggest to stick to dungeon base (only because that's my favorite ), but using traditional castle base would be ideal for an area that is meant to look like a castle. If you want something to look old or dirty, proper lighting and a few decals & particle systems here and there can drastically change the tone of the environment.

The grunge base set is visually appealing, but it isn't meant for stacking (vertically) like you're doing in this screenshot. Anyways, tips for less bland-ness in large areas:

-Break away from the traditional square rooms; use indentions in the walls (concave or convex), and use round wall shapes. Just steer clear of rectangle/square shaped rooms.
-Flat ceilings are bad, m'kay? You can use combinations of the concave ceiling pieces and flat ones to make the ceiling more visually appealing.
-Use support structures like pillars, and wooden beams near the ceiling. Not only do they logically make sense (especially for large rooms), they look durn gud.
-Pipes! If there is any sort of water based area (or whatever other reason you can think of), use pipes. There are no rules with them; the only downside is that they take a while to properly make.
-Misc.! Use rugs/torches/candles/statues/chandeliers, or whatever else you can think of.