OP, are you running a NE6 kernel with these NE6 ROMs, or are you running one of the custom kernels? So far I think all of the custom kernels are based on NB4 (TMOUS) or others pre-NE6 (int'l); I read somewhere around here that samsung has yet to release the NE6 kernel source?
Anyway, I initially started running VisonX with a NB4 kernel, and I had a number of issues with it including battery drain - seemed like it wasn't getting into deep sleep much at all. Flashed the stock NE6 kernel, wiped dalvik, and no more issues… except I still think I was getting marginally better battery life on NB4 (custom) with a custom kernel that supported intelliplug and let me tweak settings more.
FWIW this is with the NE6 modem and apnhlos flashed, but all of the other random partitions still at NB4. I'm thinking about flashing the rest of the NE6 bits (minus recovery) but waiting to hear for sure that the NE6 bootloader still supports either running NB4 software or being downgraded to NB4.
Hope this helps.