Default couple questions on Gps Acuracy.. and Xfinity streaming..

Trying to nail down some problems I'm having.. First off I've been running the same Mahdi Rom since 12/30/13 and it's been pretty flawless other than possibly a couple issues I've had but I'm wondering if they are normal with stock. 1st my Gps tracking is pretty bad. It locks on fairly quick but usually has me 50 yards off.. usually catches up but when I'm getting close to my destination it's all over the place and very unreliable. Also the proximity sensor is annoying..when I pull my face from the phone after talking to someone it stays dark and sometimes a pain to make the display come back on. Almost seems like I had these issues with stock .. I'm considering upgrading the rom but don't want to try and fix something that's normally broken. Also my Xfinity app lets me stream they're live stations over LTE and I don't want to lose this option cuz I know it's not normal.. is it just cuz I'm rooted? Any useful input would be greatly appreciated.