To answer your questions, 1. No an i5 is definitely better for gaming than an fx processor, 2. Yes you should get an r9 280x if you can afford it, it's much better than an r9 380, and 3. You should spring for the evo series SSD if you've got the cash because it's high quality, if you can't afford it though go for a Sandisk Ultra II or a Crucial BX100 of the same capacity. Other than that, the rest of the build is excellent and you should feel comfortable buying those parts.