DOOM for sure. Best FPS shooter since years.
I've been playing CS:GO for over 3 years and then i quit. CS:GO makes you want to become the best player, you get mad if someone is bad or is hacking and one match takes a lot of time. I was global on 4 accounts because i don't even know why. Or battlefield 1, its really great. Better then CS:GO if you are a casual player.
If you really wanna play something comp like CS:GO, then do it. (or overwatch, haven't played it before but i heard its great)
Also QUAKE championship is gonna come out soon hopefully.