iPod touch 5 battery draining too fast?

I've been noticing my iPod Touch 5th Gen Battery does't seem to last as long as I'd expect. Maybe It's just the way i'm using it or how i set my iPod to work. However, i'm going to mention how it is currently configured and what I use it for mostly.

Screen brightness 50%, WiFi on most of the time, Push notifications on, Location services on, usually 15 - 20 apps running on the background, Siri on and bluetooth off. Gmail is set to automatically keep me aware of new messages. All sound effects on. iCloud on for most apps that require it.

I usually play games like temple run. Sometimes I use maps and social networking apps and I use a lot the Camera app or apps that require the camera. I occasionally ask Siri for something and I ordinarily surf the web for some time. Also when I play games with intense grapics (GOF 2, for instance) the battery pretty much decreases 10% in a matter of 10 or 15 minutes (dunno if that's normal).

Last time a I fully charged it and let it drain completely, I got 6 hours, 40 minutes of usage and 19 hours, 41 minutes of standby time.

Do you guys think it's all good with the battery or should be the iPod be showing better results?