I've had end of April, beginning of October, and soon early September. Girl/girl/boy. I liked that my kids were not the oldest in their grades, but also not the youngest. My son will be one of the oldest, but since so many kids with summer birthdays are redshirted he won't be the oldest. I was a summer birthday and one of the oldest. My parents made the right decision from an academic/social standpoint, but I had to play up a year in travel soccer, which was tough, and I just always hated being the oldest.
I liked end of April best from a mat leave/personal standpoint, because I wasn't pregnant during the summer and I like to workout outside, but running in this summer heat in the third trimester is had. That said, it's nice to be able to get in shape in the fall/winter without judgement (I've had so many people yell things like "run faster" when I was trying to get back into shape a month or so after giving birth and it really sucks to hear stuff like that, especially when you are in a t-shirt and shorts and super self-conscious). Also, it's just nice to have the summer off for mat leave.