If errant members of friendly guilds are such a possible problem, couldn't you just have established rules with guilds at the onset of an alliance. Rules like, "We reserve the right to act against any alliance members that have been known to act against KgB?" Well not verbetum, but something along those lines.

Have to agree with the importance of reputation, in a full loot server, it would dictate a lot of what happens.

Former KGB Member