City(castle, siege) and ruin maps are best in my view.
Village maps are nice; since I like full immersion, in certain states of mind I may find myself felling trees and forking cabbages instead of seeking the enemy team and using teamwork with my own.
Protip: Work WITH the terrain not against it and you can go very far indeed; not every detail needs to be smoothed out, sometimes the terrain generator can work wonders.
A mix of styles is best, all the greatest maps use a careful blend of styles. Pre-plan what you will do before you do ANYTHING or at least make use of the terrain colour feature to block out certain areas as being a type of thing or responsible for a certain play-style or feel.
any map which you can ambush people from above like batman is preferable
Literally 'getting the drop' on other players feels and looks fantastic; as the sky-box is criminally underused in most maps, please use this feature more.
My map "2Desert" was an experiment with the available height of maps and is the smallest available setting in the terrain editor.
Just my 2 paragraphs.