Tips for Displays:
1. Think Big: you want something that will look impressive from far away.
Sometimes that means going smaller rather than going bigger - ie, if you're doing a wall town - only make one that is big enough to enclose your houses (plus roads, details, etc) - don't make a big walled town that is virtually empty inside.
Also include a central focus point that is taller than your other buildings - like a main tower, a windmill, etc - which will be the center of your display. This is what will draw the viewer to your display, which will lead them to the other elements of your work.
2. Think Small: if it is the big things that draw them over, it is the little things that keep them there
Basically, thinking small means details! Details of each and every sort. From the usual things like trees, a cobblestone road, and villagers to signs on your various shops.
Minifig details are one of the basic elements that will connect with your audience. I'd divide the minifigs into two groups - the first is the non-active figs. These guys will be walking around, looking up or down, standing - basically, they are filler to make the town look like a town. If you are doing a battle scene, these guys are either running or standing in formation. The second group is the action figs. Create pockets of space where the action figs are noticable (that is, not really close to nonaction figs).
Then you create the action-detail. Have a duel between two knights, or a juggler juggling - or a drunk drinking brandy - or a medieval dentist - or a band playing music, or a prince wooing a princess from her balcony. This is where you get really creative with the details that they are holding (like Nathan's Instruments, or a cool Lil Armory sword, or something else).
The key with rules 1. and 2. is to think of the display like a Macro-MOC - you want the same sort of excellence and detailed quality that every individual MOC has.
3. Don't sweat what can't be seen.
Many castle and space builders take a lot of time and effort to give their creations detailed interiors - but when displayed, this effort is hidden by the hull of the spaceship or within the walls of a castle. Unless you want to have a castle permanently open or you wish to open it manually for everyone who walks by, then don't waste your time doing those time consuming details.
Spend that time working on details that can be seen out in the middle of your village.
4. Create a barrier between your audience and your work.
Since we're talking about LEGO toys, it is the automatic reaction for anyone (adult and child) to reach out and touch the creations. Sometimes kids who don't know any better try to pocket some of your figs, or sometimes the adult unknowingly breaks the roof of your MOC. The way to avoid this is to create various types of barriers between your MOC and your audience.
This can be a simple as 5 inches of blank space between the MOC and the edge of the table. Even that little bit of area helps give the visual clue "don't touch." For larger displays stanchions are a good idea (the little poles with rope that you see in banks, etc). If you don't have enough to go all the way around, then you can create a 'one-sided' display where you stand behind the table, your audience stands in front of you. You need one fourth as many stanchions then.
Also, make signs that say "don't touch" - these can be combined to identify who you are as well.
5. Be prepared for questions
People will ask you the same sort of questions constantly:
1. How long did this take to build?
2. How many pieces did you use?
3. Is this a set? Can I buy it?
4. Where did you get all these bricks?
5. Do you work for LEGO?
I hope your display turns out well, and I hope my advice helps! I'd love to see pictures when you're finished!
"The sound of laughter is like
the vaulted dome of
a temple of happiness. "