It would be really cool if every twenty-four hours you could grant every player in your clan three, five minute production boosts to collectors or 5 minute upgrade time reductions. These boosts that you would send your clanmates, and your clan mates would send you would be accessable from each players mailbox.
One REALLY cool aspect to these production boosts is that each day, you would visit each of your clan members bases. This would help you to keep tabs on the clan you are in, and gauge your friends progress. Similar to searching for battles in pvp, you would scroll through your clanmates bases (so you don't have to view their bases individually, you just scroll through, tap 3 times on their collectors or upgrading units, and then scroll on to the next and the next base...)
I saw this in another game I play which I will not name to avoid controversy. But anyways, this would be a nice addition to Clash of Clans, bringing you closer to your clan, adding a new thing to do in the game, and also rewarding players with a few hours of free production boosts each day
This would cut down on supercell's income, tho make more loot in the game. I think SC cares more about their money than COC's virtual money. Don't see this happening.