To be honest, only you can really answer that question. We have no idea how many games you own or currently want to download and play.
Your OS and programs will take up about 50gb of your SSD, so that leaves you with 200GB to play with, with your average game these days taking up 15gb. So, thats enough room for about 15-16 games (though games like Total War, Battlefield, WoW etc can reach up to 30gbs on their own).
So its really down to you to decide whether that's enough for you
