My summary/opinion

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Alright, many of the ideas suggested revolving around having clan info and stats available in the lobby are very nice, but as far as clan requirements go, there needs not be a complicated process to form a clan. Having a required number of members is a good idea, for reasons stated before, but clans are best when they have some freedom from the game itself. I am sure people will know which clans are the true, long earned/lived clans just by participating in the game regularly.
also its hard to measure use of tactics as Staruk said, once again i think players will be able to reckognize this ability...
also i agree with wedge's 7day war (or other timelength).
an integrated section for stats and clan interactions as suggested is also handy