I would certainly recommend the Pegasus kits.
I used them in my ruined Mordheim church (which will also be used for Frostgrave at some point).
Easy to add to too.
The roof sections are cut up dolls house roofing and balsa wood.
Some pics of the corner sections;
The Shrine of Aquila from GW blends in quite well with it too...
More pictures of it here:
http://leadadventureforum.com/index.php?topic=30667.0