The big issue in my opinion was that is no configuration changes backported to 4.3. For example, kamailio and freeswitch updating almost every week by Luis, and nothing released for 4.3 for a years. Centos 7 will be soon end of life and will not receive any critical patches anymore. I personally don't care about market place at the moment, will be nice to have it at some point, but for me is most important to get improvement in voice quality, stability and features. I'm pretty sure that freeswitch and kamailio get whole bunch of new features for last couple years. James is the only person who support us as much as he can and I appreciate it very much. Unfortunately I don't see other knowledgeable people from a team like JR or Lazedo in IRC or here .
Just my 2 Cents...