I can help you out alot on this. As I've tried it all. You want to control your GPU just as much as your CPU since you mentioned your desired speed playing games. I have my GPU set at 400 mhz performance instead of 300 mhz. This is gonna help you alot playing games changing your GPU from 75% or so on demand to 100% performance.
3c Toolbox Pro (This is what I currently used CPU controls, kernel tweaks, system manager, entrophy,sd card, oom settings. This app has it all including scripter, terminal, etc etc and profiles and tasker schedules. If you want it all this is the app for you. They also make 3c toolbox which is free but less functions. The same company makes System Tuner with the same CPU functions and GPU functions as 3C Toolbox
There is Rom Toolbox pro and Rom Toolbox lite
Kernel Tuner
Fresh out of the box brand new one is Kernel Toolkit it was made this year I believe and has a rating of 4.4 in the store I think it was made in Febuary. Its a full out free tuner Cpu,Gpu,I/O and.
Trickster Mod is another one but older I believe but respected. Same for SETcpu its respected but hasnt been updated in like 2 years. It does actually work but its basic but if all you want it CPU and GPU settings it might be for you. But if your gonna mod why not mod all out like 3C Toolbox pro.
3C has preset options where you dont have to input anything yourself if you dont want to like Build Scripts and Sysctl tweaks.
Since you refered to playing a game in your OP I suggest you go all out. Hope this helps. And don't be scared to ma out the cpu and gpu with performance govs. My device cpu has never gotten over 139 degrees farenhieht and I'm a power user.
Hope this helps
Josh