Hmm, I was hoping I wouldn't have to do a reset but it seems there's no other way. I had already reset data / cache for all IMS related apps but it didn't help.This time, the wifi is constant, no drop offs. Other than that, there is no other improvement. Mobile signal was also better this time.
Regarding apps, I had already listed those that cause drain, chief among them being IMSservice. No different now.
So your wifi issue is not due to your router. It must be the kernel because it causes kernel wakelocks. You seem to have exhausted all other options except for a clean flash. Or may be a different ROM with a clean flash.
I am suspecting outlook might be causing issues. I'll try uninstalling it