The 3570K is very comfortable at that speed and voltage. You could go a little faster but voltage will need to go up and up very soon so not really worth it to go too much higher for 24/7.
The sensors are not 100% accurate so idle temperatures are not very important. Your gaming temps are fine.
Real Temp T | I Editionhttp://www.overclock.net/t/1330144/realtemp-t-i-edition