There really isn't an optimal VPN for gaming, 'cus it'll mainly suck all across.
Best option is to find a VPN service with a server as close to your location as possible.
Like a ~50 mile radius or less.
Cybe****** is good. But for the game I play it is IP-Banned..
Hotspotshield pops-up ads randomly..
Zenmate is fine, but the server is unstable sometimes.
Betternet is atm my best choice... Stable but without the location I want..
Erm, don't see why you would need a VPN on playing games, unless you're IP banned on the game or something, but I would personally go with any company that's near you, or you'll get shit ping. (From personal experience).
Encryp***** have been good so far in my experience. As they have an option that automatically enables the fastest server based on a range of factors. But as others have already stated; the closer it is to your location - generally the 'faster' it will be.