I am 5' tall, 100 pounds, boot size 7 (mens), I like freestyle and am 12 years old, and lastly I ride in PA so the hills aren't super powdery
Considering where you plan on riding I suggest you look at boards with camber or hybrids with rockered tips and camber underfoot, in the size recommended by the manufacturer. Personally, I wouldn't consider a full rockered board due to the fact that you will be riding mostly on groomed ice and the board will likely see little if any powder. Check out Ride, Rome, Capita and NeverSummer.
I am an intermediate rider as well but I am much older than you (30). That being said; don't discount K2. I went from a regular camber 2004 M3 155 to a 2010 K2 Jibpan 153 with rocker camber and it is like night and day. I was progressing slowly over this season until I got that new board. My skills have increased 100% in the last 3 sessions because the board is the right size and fit for my style of riding.
Also I don't entirely agree with the no rocker because you ride groomers. I live in Michigan so all I ride is groom and the K2 rocker hasn't presented me with any issues at all.
i live and ride in pa and use a 2010 hero wich is full rocker and have no problems on groomers so i wouldn't rule them out for that reason.
I agree, I wouldn't rule it out for that reason either. In fact I ride mostly in PA as well, with my custom v-rocker. I rode it yesturday at Camelback as a matter of fact. But for jumping, bombing and carving on ice I prefer camber (my Ride DH). Rocker is also very forgiving; it doesn't make you pay for bad technique like camber does. From personal experience I suggest learning on camber.