I'm a "science person" but here's my advice anyway:
1) Funding for me would be HUGE. Unless I completely fell in love with a more expensive program, this would be the most important to me. Not having as much debt will be much easier for you in the long run.
2) Location is important. I didn't apply to any schools in areas I knew I wouldn't want to live in (NYC, for example). You're pretty much choosing this place for the next few years of your life- make sure you can at least tolerate it.
3) I wouldn't go off rankings. A lot of times, they don't really mean much. From what I'm told, where you got the degree (to a certain extent, of course) doesn't matter - its what you did while you were there. Do any of your schools have stand out internship/experience/etc programs?
My last bit of advice - trust your gut. I know it sounds stupid, but when I chose my undergrad, one just felt "right"- even though it wasn't as high of a ranking. And I've had experiences here I would not have been able to have elsewhere.
Hope this helps! Good luck!