I think no need to w38. W37 is stable enough to use daily.
Devs should work on cm12 :)
There are still development and fixes applied to CM review.cyanogenmod.org/#/q/status:merged+branch:cm-11.0,n,z so we could also profit from it....
Can some of the defs create a new 4.4.4 release with the updated sources of bluez as i saw they are already merged (https://github.com/XperiaSTE/android_external_bluetooth_bluez -> revision bluez-master) and a2dp should finnaly work.
A2SD is fi...