As per this request http://www.wargear.net/forum/showthread/2035/Make_team_message_the_default_in_team_games two options have been added to the Settings page allowing you to define the default message taget for teamplay / non-teamplay games individually. 

It's very good, especially for team games where you most of the time write to your team.

In non-teamplay games, in order to avoid sending to the public some private messages, I took the option of self-messages as the default setting. But I find it very frustrating when in 1 vs 1 games. In this case only, I would prefer the default message target to be a public message as I almost never write to myself. The more you get, the more you want...

Hmm I'm not convinced we need another option - it gets to the point where you have so many options it gets confusing and I think this might be a step too far! 

I understand. It's not a big deal anyway. It could also not be an option. I mean the default message option would apply only for game with at least 3 players.