I'm pretty sure Carbon lets you dictate button actions, but I can't remember. I went straight from receiving my tablet onto Carbon, you're observed battery life sounds like its better than I have achieved. I usually get about 4 days use out of it, and about 5.5hrs SOT.
Moto X (1053) -
retired Nexus 5 -
Carbon'd ElementalX v.36 2.9ghz/300mhz, Galaxy Note 8.0 -
Carbon'd KK, Nexus 4 -
Nook HD+,Motorola Atrix 2, HTC Aria, Nook Color
, Nexus 7 16gb - Sold