In good weather, you can effectively double your party space by including your outdoor living space.
Decks, patios, porches and yards can all be included. Supply some chairs, lanterns or candlelight (if it's nighttime), music and snacks, and let your guests know that they're welcome to move outside. A weighted, lidded garbage can is also useful to include.
Outdoor firepits or fireplaces are wonderful focal points for outdoor functions, and guests love to sit around the warmth and chat.
If insects are a problem, set up citronella-burning tiki torches or candles throughout the outdoor party space, use a Mosquito Magnet (needs 3 week lead time to control the mosquito population), or use a 6-hour outdoor fogger before your guests arrive.