Definitely agree that the 64GB is worth the extra room. It's unfortunate how much of a steep jump on price there is between those two sizes. Definitely just a case of "we charge that much because we can" on any phone manufacturer's part.
BTW, I actually just noticed that
the company I've sold a few iPhones to charges way less (maybe $25?) between a 16GB and a 64GB phone. As someone who has sold phones only, I noticed because I was on the losing end of this. But if you're looking to buy, it might be a better option than buying new.