You'll find that simultaneous game communication is too slow. By the time they get your message to "remove your ships or else" you'll have already killed them
E-mail contact is usually fine assuming you can find their e-mail address.
Other than that, most games have their own Forum on the PBW server, and I notice that some also have forums here on ShrapnelGames.
As for suggestions, well I can't really give any.
My play style changes with every game and I'm still trying to find my favourite
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The Unofficial Space Empires 4 Mod Utility V2.0
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Download as a .ZIP <
HERE>
Download as a .RAR <
HERE>
Download as a .ACE <
HERE>
Check a Screenshot of it<
HERE>
Check an Alpha Shot of my Mod Editor (Unreleased) <
HERE>
My Geekcode : RNmPeOr MpPi2!+ Rp++ Tcp+ Fq+++!@ M+++ Fr= P+? A+++ Sf= T++--
Checkout your Geekcode :-
.Zip <
HERE>
.Rar <
HERE>
.Ace <
HERE>