Hold on. I can appreciate that you want to isolate PSR-2 changes and/or have different format preferences, but if you mean to say camelCase is in conflict with PSR-2 you'd be wrong. At least, according to the documentation on github using camelCase for variables is not in conflict with PSR-2 or PSR-1. (https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-2-coding-style-guide.md)

PSR-2 is entirely silent on whether variables should be written in camelCase or underscore format, and PSR-1 explicitly leaves it unspecified. One of the PSR-2 examples provided on github (in section 6 on closures) actually shows usage of both camelCase and underscores.