The same methods used on older IOS jailbreaks might work , browser based vulnerabilities may not be the best move but if we were able to modify an app that can be installed to system with certain permissions with an embedded program similar to a DLL windows file exploit it might work , or instead of flashing a custom bootloader why not add some more options to the inbuilt if thats possible with the dumps that have been curated these past months , another idea if we can find someone over at XDA to write a virus that takes over the phone but instead of stealing user information it dumps the phone or , compile a fake virus scanner that can retrieve information or dump to system , but I feel an embedded app approach could work - I'm just a tinkerer not a developer