I honestly don't think it's worth it. The screen is AMAZING, as you'd expect, but keep in mind that most websites and programs aren't formatted for that huge of a resolution, so it makes a lot of things blurry.
720p on YouTube is honestly just the lowest you would want to go because the amazing screen makes everything normal resolution that would look fine on a normal screen look bad.
I don't think it's worth it, you can get good specs with a SSD (a smaller capacity but much faster hard drive) for a lot less than $2,700 or whatever it is.
I know a ton about Apple products and own 20+ of them myself, from iMac's to Mac Mini's to Macbook Pro's to Macbook Air's so if you have any further questions you can PM me.
I'd say, if you want the 15", get that with an i7 processor, at least 8GB of RAM, and a 256GB or 512GB SSD.
If money isn't a problem, go big.
That's my two cents.