My advice: don't count out power saver mode
To my knowledge, power saver mode limits you to one core and turns off data connections when the screen is off.
This might sound unappealing to some (after all, quad-core was one of the biggest selling points), but it's not so bad when you consider that each core offers 1.7ghz. This should be more than capable for most of the things you do on your phone (if you seriously intend to game full-time, there's other devices much better suited for that...). Need more juice for a game? Turn power saver mode off... game... then back on again when you're done.
I really think "power saver mode" was a bad name choice. My personal opinion, they should have labeled it "performance mode" where all of your cores would be enabled after being checked.
I think people would feel less inadequate when putting their phone into power saver mode, making this mode "normal mode". It would also be more of a treat whenever you needed to enable "performance mode", instead of feeling let down whenever you have to go into "power saver mode".