Debloated, optimized, stock ROM

Guys, I've looked through the threads here but I can't seem to find a rom which is stock, but debloated and optimized. I am on CM11 now but I am experiencing very bad battery life and some instability. I will be passing my S3 to my daughter soon and I would like to have a stable rom with good performance and battery life. It would be best if the ROM would be a modded stock rom which includes the factory languages, Icelandic to be exact :)

Can anyone point me in the right direction? It doesn't need to be Kit Kat, just a stable and fast rom.

Thanks!