no expert but i would back up the idea of a larger SSD
SSD's are the best upgrade you can buy
Idealy you will want your operating system on it as well as the game you are playing
Don't short yourself. Most times buying a "smaller" SSD storage size and than buying 2 or 3 matching SSD's is cheaper than buying one "larger" storage size SSD. It also lets you parse out your files to put your OS on SSD1, while using SSD2 through SSD4 for "ACTIVE" games that require serious amounts of accessing files for rendering assets. Just don't make the mistake of purchasing to small of a SSD to where your OS won't fit on a single SSD.
1) CPU Cooler: I personally don't like a single 120mm fan on my radiators. I prefer twin "Push/Pull" 120mm fans to ensure the radiator is fully cooled under high duress from core CPU case temperatures. It as well decreases the rate of evaporation for your sealed resivor. Remember, once your resivor is depleted, you have to buy a new cooler unit.
2) CPU Cooler Water Block: I personally prefer the Intel water blocks over most of the other blocks sold as full units. In my research the Intel water blocks have a higher degree of 4 axis machining rather than being a billeted multi piece that is thermal welded together. You can find cooling setups where can purchase the radiator/resivor and fans as one unit with the tubing and the water block separately.
3)RAM: 8GB of matched RAM isn't enough.It looks like the gigabyte board you selected is a 2-Channel (RAM slots). If that is true, you have two choices. Change boards, and get one with 4 Channels, or upgrade your RAM to 8gb each sticks instead of the 4gb sticks you have listed.
4)Case: Nothing wrong with the case you selected, it fits the degree of hardware you choose. No sense in getting a super case you never intend to populate. Here is where preference comes in. I really prefer the Lain Li computer cases over almost any others. While I did buy a new Antec case a few years ago when I built a new rig, I still have my Lian Li full tower and have yet to see any manufacturer really be able to touch them at the price points they offer. For upgrade purpases of a larger video card at a later date you might want to consider spending another 40 bucks and getting a full tower that will accommodate the "HUMONGOUS" GPU w/ Coolers that are becoming the norm. I suggest this one Lian Li Full Tower $190
5)CPU: You spent high dollars on your CPU, but the Mobo they packaged it with is a bottleneck. You have a couple of choices. You really don't need anything beyond the i7 3 series CPU's with the "k" series so that the cores are unlocked and you can choose to overclock it if you really wanted too. "Down grading" your CPU to 3.4mhz is more that any game, even a full blown on mega steroids Star Citizen will ever need for cache computing. Your chip isn't going to be your bottleneck anymore under the current architectures. The bottlenecks are now RAM Slots, Northbridg and SSD vs Traditional hard drives. You could use the money saved on slightly downgrading your CPU to purchase a better MOBO which will give you probably 4 RAM Slots vs 2 RAM Slots and be a better northbridge able to push more data across it.