The current PM system is quite limiting. I think that there needs to be an easier way to add people to the message recipient box. Also I think that it would also be restrictive if the max recipient limitation also applied towards staff. I haven't tested that limit, but it might have been an oversight.
1. Access a drop down list of our friends and be able to add them to the recipient list.
2. Create custom PM groups or at the very least have direct access to the list of members in our special usergroup.
I've recently received a PM sent to all Support team members. I can't really send my reply back to all members and it's cumbersome to create a mass message to other group members.
3. I really hope that we're not restricted to 6 participants. Our group has 7 members already. If we add one more then we cannot add everyone in one PM.
4. Include the user suggestion ability from the user search text box to the recipient textbox. It would save time when you don't have to fully type out a name you might not remember how to spell. adding this would make it easier to add friends/fellow group members without the need for special group access lists.