Definitely the headset! My current one is a few years old now and it's beginning to fall apart. I really like the style of the H6PRO, and the features are far superior to my current one!
I've had my Razer Naga for about ten years now and it's still going strong, so I'd probably give the mouse to a family member... I'd keep the headset and keyboard though! This game looks cool. I really like the art style