Default [Q] CarbonROM, Clean Installs, and App recovery

So I'm on the gNex(toro) and searched but mostly found old threads (even the similar threads listed as I type this are from 2010). Wondering if there's anything new, sorry if these are repeats.

1. Is CarbonROM based on CM or do they pull some things from CM? I know Carbon has a changelog, but should I also follow CM's changelog for changes in CarbonROM?

2. I mostly dirty flash, but would like to clean flash more often if there's an easier way. Right now I factory reset, flash Carbon, GApps and kernel. Then Titanium from Play Store (and stop auto downloading) to restore apps so that I'm not downloading a couple GBs from the Play Store every time. Is there a better way? I'm using TWRP 2.7.0.0 if that helps.

Thanks.