I was accepted into the Spring 2018 cohort and I had a really hard time shortening my essays and choosing only 2 as well. If they say to answer 2, I would only answer 2. They most likely will only read the first 2 if you submit more than that because they have to get through so many applications and it wouldn't be fair for them to read more in your application compared to other applicants who followed the instructions. It's incredibly challening to narrow things down to 300 words, but they want to know that you can write concisely and get your point across. Short, sweet, and to the point will be more memorable than writing a novel. I couldn't choose so I had a few of my closest friends and professors read all 3 and vote. I hope this helps! Best of luck to you!