If you build a ship that accelerates at a constant 1g towards the destination until the midway point, then decelerates at a constant 1g, due to time dilation, the people on board would experience "only" 12 years passing for a 700LY journey. People on Earth would still need to wait 1400 years for the first communication back, of course, but at least you won't have to build generation ships.

Edit: I got my numbers from http://convertalot.com/relativistic_star_ship_calculator.htm...