Honestly, there's very little I would change about my sorority house. It's not too big, it's welcoming, and it feels like home. I love our porch swings, and our amazingly comfortable couch, and I really can't imagine another house being so "us."
That being said, however, I would love for there to be more girls living in the house at any given time. Also, more space for crafting stuff, and a bigger kitchen would definitely be a plus
ETA: My school doesn't have a sorority row, the houses are spread out throughout the campus area. Part of me would love to have that kind of environment