I'm impressed... great concept.
I've uninstalled JD to see how this works for me. My first impressions - apart from the vastly improved deep sleep time of course - is ease of use (JD is diabolically complicated, at least for me...).
One thing I do like from JD though, is the ability to program the sync frequency of "syncable" apps - there are about 6 options, including 1hr, 3hrs, 6hrs, 24hrs.
I found this very useful since I would let Whatsapp (contacts not messages) and Google contacts sync every 24 hours, Google calendar every 3 hours, weather every 3 hours etc.
I use Kaiten email push to receive my emails: being push, they arrive every time the data connection is restored. So that option described above really cuts down - I think - on phone activity, compared with linking the sync to the wakeup period, or letting them sync as they want to.
Could that be done in Deep Sleep Battery Saver?
Nexus4 4.4.2, ROM: Purity 7/02/14 build. Kernel: hells Core b46t4. Radio:98