Fully agree with harigov.

It would be recommended to charge for Cyanogenmod instead of giving away the operating system for free.

Further it would be recommended from a revenue point of view to support the Android devices with the biggest user base. Samsung, Huawei, Xiaomi. These devices should be super easy to upgrade.

Smartphone market share http://www.idc.com/prodserv/smartphone-market-share.jsp