In backyard monsters, it seems like your neighbors are always around the same levels as you. While you can't really play and not earn EXP, you can try to limit which EXP you get. For example, attacking neighbors will give you resources, and attacking the town hall gives you no resources but a ton of EXP. (However, if you don't destroy the town hall, technically you have lost the battle).
Should you try not to gain EXP in order to keep yourself surrounded with low-level neighbors? Is this a good strategy?