Looks fairly good but IMO jail breaking and leaving open unknown sources can leave potential leaks and vectors of attack to your device. Updating is highly recommended.
Yeah. I wasn't really sure if that version of Andrioid was the latest. I mean keeping a phone updated is like the same as the computer. Applications = java (exploitable if not updated Android = PC (exploitable if not updated when needed.)
Yes it works, "Unknown Sources" just needs to be enabled at time when installing Adguard and opening dl link from android browser since its not available at Playstore Adguard for Android download - the world's most advanced ad blocker I have also removed field "I install apps that are published outside of the official store" to be precise
Everything is fine, it is a typical reminder of having jailbreak/root open because of security issues but in reality attacks; it's very minimal at all.