I'm also a prefrosh, and at CPW I went on a couple tours of East Campus (it's also my first choice) and saw each hall. I actually wouldn't worry about each hall yet - we will get to see that all during REX. Each of the halls are really different - like I loved first west because it was really chill and people played guitar but then third east seemed really fun. It's difficult to define each one without living there yet, maybe try posting on the facebook group? I'm sure one of our current students there could help!
And for more information, the website is actually really helpful. If you click on each of the halls here East Campus Halls
it takes you to the website of that hall. You can tell from the descriptions how serious each hall is about everything (and also how obsessed they are with painting/hacking/standardmitactivities) but honestly visiting is the best thing you can do, it feels awesome to walk through those halls in person.