Dazhai is a bit further but fewer tourists and majority (though not unanimous) opinion says somewhat more impressive than Ping'An. Most day trippers are in Ping'An area. Do some internet searching on specific guesthouses there. Best would be to get to Terrace location of your choice by early afternoon so you have the afternoon to hike and photo, overnight, then early to mid-morning the next day for different lighting. Get butt out of bed early to grab the sunrise. Onward by around lunchtime to Chengyang--you don't want to wait too late since transport options taper off as you get deeper into the afternoon. Done this way, one night at the Terraces is enough for most people. If you can't manage Dazhai or prefer to do Ping'An, that is also OK.