First, since you are about to flash back to Alpha5, it wouldn't hurt to download a fresh zip of beta0 + fresh gapps...........am assuming you still have a Nandroid of CM9alpha5?............w/ your issues (shouldn't be any of those things happening on beta, btw) I would: (1) backup callogs + sms (2) boot to CWM recovery (3) wipe cache + dalvik-cache + wipe data/factory restore, THEN restore CM9alpha5 from the nandroid..............from there, all things being equal (good battery life + stability that you've referenced), I would power-off then boot back to CWM recovery, wipe cache + dalvik ONLY + flash beta0, immediately gapps + boot to system...............all of these procedures would perhaps take an additional 20 minutes............+ you can always restore your Nandroid of CM9alpha5 a second time in the event that CM9beta0 is still behaving erratic.
Some thoughts for you TH (just a start as there has to be some specific cause for all of the irregularities on this beta affecting your device,)............OH, if you don't have a nandroid of CM9alpha5, why not wipe cache + dalvik ONLY your first time flashing back to alpha5...........if your issues appear to have gone along for the ride, you can do the TOTAL data wipe w/ next flash