I uninstalled all user apps and installed only the few which I really rely on. One by one, checking after an hour or so, if miscellaneous drain is in the stats or not. If yes, app uninstalled.
Might be some root apps, but possibly also user apps which aren't L-ready and hence not classified.
P.S. In before a reply:
Yes, it is a developer preview, I know that...
The reason no one is putting an effort into L preview issues is that for one... It's a preview... Could have issues at this point we would never even think of. And, official L is right around the corner. Annnnd, without being able to see the wakelocks, finding many common issues turns into looking for a needle in a haystack.
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