Is this a good first build? Anything to swap out or change? How many fps will I get on league of legends with this?

Solution
Agree, you don't even really need a K CPU for gaming, rather save the money there to upgrade at least to a 780, this will give you much more appealing gaming performance, or put the saved money into a bigger SSD/HDD. But if you want to OC, there are better options than the H100i, especially tower air coolers which will allow you to get the same performance as with the H100i while remaining way more quiet. And even if you want to keep the 4790k, there's absolutely no reason for the Maximus unless you absolutely need its features. There are cheaper, good OCing boards.
Agree, you don't even really need a K CPU for gaming, rather save the money there to upgrade at least to a 780, this will give you much more appealing gaming performance, or put the saved money into a bigger SSD/HDD. But if you want to OC, there are better options than the H100i, especially tower air coolers which will allow you to get the same performance as with the H100i while remaining way more quiet. And even if you want to keep the 4790k, there's absolutely no reason for the Maximus unless you absolutely need its features. There are cheaper, good OCing boards.
 
Solution
I second i7baby. Everything's OK, and with a 770 you'll get around 45-60 fps with AAA games on high-max settings @1080p. I too would get an i5 cooled by a 212 evo although, and unless you're into overclocking, I'd get the non-k version to save those extra 20 bucks. Get a 780/780ti for better future-proofing, and although the 650w is fine, I'd get a 700w just for the ease of mind.

As per peripherals, Razer is like Apple: quality products overpriced to the max...
Some Steelseries, CM Storm or Roccat pieces, to name something I tried myself, usually have the same quality while costing a bit less. Played a couple games with the pieces you posted off a friend and played the same with my Roccat ARVO keyboard and my Steelseries Sensei RAW mouse. No noticeable difference.

Edit: and due to the fact I'm on mobile, I keep typing so slow that answers get useless fast 😀