Is the cooler a bit excessive.
if you are not sure, go with a strong air cooler. liquid cooling may degrade quality, pumps get noisy, etc
Is the motherboard I selected good enough?
Is the GPU any good because I can't find any reviews?
no, XFX often cannot be OCed. get gigabyte/sapphire
Is the case good enough for the build?
your case is expensive.... but it is a very good case
And what is your overall opinion about the build?
your cpu should be 3570k as it performs similar in game. i7 only benefit in professional software