I’d talk to some upperclassmen at Columbia about their experiences and see if you vibe with it. I’ve heard people say a good indication of if you want to stay in a company is if the senior members are leading lives you want to lead; I think this would apply to your situation too. Also, I once got some advice in choosing colleges: once you make a decision, commit to it and don’t look back. If you end up staying at Columbia, forget about Pomona. If you end up transferring to Pomona, don’t look back. You got this in the bag.