recommend stable and battery friendly rom for s4 gt-i9505

suggest/recommend best and stable rom for s4 gt-i9505.

S4 GTI9505 flashed recovery without root help

So I accidentally flashed the recovery package through Odin to a friend's s4 gt i9505 and i get a no access error in the recovery with an android and a red triangle. Since it has a custom recovery odin doesnt detect it. My question is what should i do ? :confused: . There is literally noone that has experienced the same (noob) mistake so there is no real fix. The phone is running 4.4.2 with an official upgrade to lollipop but KNOX was tripped so I would like to fix for him without having to pay for official service.
Thanks in advance.

Soft bricked Samsung Galaxy S4 GT-I9505

http://forum.xda-developers.com/gene...i9505-t3212975

https://www.reddit.com/r/AndroidQues...xy_s4_gti9505/

I've tried almost everything possible, (those two threads above were made by me), but I'm still not able to reach a solution.. please help me.