First, thanks for bumping the CC limit to eight. Much appreciated.
What's not so appreciated is having to type all those names in every time I hit reply. :/ Unless I'm missing something, there's no shortcut to do it, and it doesn't happen by default.
Would it be possible, then, to add a 'reply all' button to the options for PMs? It would have to respect (i.e., not include) BCCs, but all recipients and CCs could be on it.