I had CM 11 for a couple weeks. Battery life didn't seem to improve and several LG software features were missing (quick memo, slide aside, etc). If you're looking for an AOSP ROM with great battery life and lots of UI and performance features then I suggest PAC-man, Carbon or SOKP.
dont use quick memo or slide aside really, im just wondering if you felt like it was lacking. did you got back to stock after? why? and did you try hotspot with your carrier on CM, did it work?
I didn't think CM 11 had any major issues, but I ended up using other custom ROMs (carbon, SOKP, Vanir) for more UI and performance features. Hotspot didn't work with AT&T and CM 11 Nightly.