Firstly congratulations on getting two offers!
Yes, it is a difficult decision. I agree that a list of pros on cons for both universities will be helpful. I did the same thing when I was choosing universities. And as people always say "follow your heart".
Another suggestion that someone gave me before was to flip a coin, assign heads and tails to each university, and when you get the result, reflect on your immediate feelings. If it's a relief that the correct side of the coin came, it suggests you prefer that university; and if you feel disappointed in the heads/tail outcome, it means you probably prefer the alternative one. Perhaps give this a try in case it helps.