Rusty, I'm not too sure about that... I've never heard of a clan where 50% or better are on the forums. My clan's forums are very healthy compared to what I've seen and I'd say only a third of my clan actually posts. It's tough to get people on the site, but once they're on and see it's not that bad they usually post more after that.
As far as addressing the xi's, someone said you should start with your chain of command. Using your XS, XD, etc.
I know of a few times I've brought ideas up to general's and they've been like "nope. not gonna happen. [big speech about why it won't happen]. so, ya see, it's a bad idea." and then it gets dropped like a backpack full of bricks. The XI's can say to the person below them "hey, make this happen," and it will happen.
Simple ideas that have popular vote behind them shouldn't get shot down if it's not going to hurt day-to-day operations... so, one's best bet is to msg the XI's straight up. If this were a problem, the Honor Code wouldn't have the "Open Door Policy" that clearly states that issues can be sent up to whomever. Granted, simple, menial problems should be handled at the lowest level... but when one of my guys has a big idea, there's only so much I can do about it.
In some cases, an XS/XD can be your worst enemy. Some of them, especially the key ones, you know are going to do everything they can to stop you in your tracks.