I thought about someting like this, but didn't discuss it with server owner:
f.e. every Monday, 7 PM, we organize ourselves and go play on the server with enormous squad, no noobs at all (dont know how to deal with reserved slots, but no worry). Some invitations maby, maby server password, dunno, lots of possibilities.
We could make teams and team leaders, give each team a forum section to discuss their tactics to next game, make f.e. 8 teams and play a... league. Matches. Like clanwar, but all players are collected from forum members. I guess that it sould be done like that:
server is not passworded, but when squad_member that has a 2h match from 7 PM can join it as a reserved slot (kicking someone without reservation) from 6 PM to 9 PM. Teams are (as I imagine, but it can be lower or higher) 10 to 12 players, notice that there is still a place for someone to join the server and game is not strictly "closed", it is public (so we are not moved to private servers category in any server rankings :P ).
Squad leader is able to add/delete a squadmember by steamid, then it is added by some script to forum section access automaticly. You can be in 1 squad only. You cannot be on the server while the other two teams league match is on.
I just think loudly, feel free to comment.
My point is to get a dream team and a dream teamplay. Every marine knows what to do, has whole tactic in his memory, commander is just a tool, he knows exacly what to do because it was discussed for days on the board. When something happens (f.e. onos passes defences) comm says "ANTI-ONOS 3-7-1 A!" and all of them know what to do, 4 top players from the scores (not counting commander) goes after onos, 7 attacks (A=attacks, D=defends) front, one stays base to take onos down if 3 marines push it that far. NO. 3 marines go from the front to the base, one goes from the base to the front, onos has to die.
Teams train by the week, they check tactics to gain 2 seconds on building a proto, they plan how to build RTs (all go to the left RT and then all to the right in acid room on ns_space_cow_ranch, or they split, half go left RT, half right. This can give 0.5-1 res more if done properly). Things like that.
Aliens doing amazing things, like gorge jumping on skulk that climbs a wall, so gorge can throw bilebomb few meters longer... Anything You can imagine and train all the week, will give You advantage in the league match on monday (f.e.

).
So it is not a clan, but cluster-clan in my version. What You say?
EDIT: teams may be coloured, green team, red team, blue team... Team members can glow the proper color (I can do that with amxx if Moron sends me some code i think). They can glow or not glow on public games and/or in league games. Plenty of ideas like that. Need community and headadmin to say "good idea, lets do it!".