Its not the jb, its a tweak/app you installed.
The jb is fine, its NOT in beta, tweaks on the other hand...Yeah i would say the jailbreak is still in a BETA like stage. Possibly some of the tweaks still need to be updated to work properly. I use the Zeppelin tweak myself from previous JBs. works fine on my iphone 6 but not the case with ipad air 2 (so its removed) causes the cydia bombout on pangu ios 9 JB. Everything was fine before on Taig ios 8 JB.
Pangu Untether 1.1 update, improves reliability and Bootup process (BLoD issues), also ios 9.1 is released, I wonder how long before 9.0.2 is stopped being signed/available. NO 9.1 JB available currently.