All good questions. Part of the problem is I am too tired to through all of them and see which are on and which are not. I think the #1 is with the II folders. There really hasn't been a lot of opportunities for AC to add any. Most updates have been rather specific.
When you look at the list of 81, you also see about 30 comments or so of others adding ideas. I can also say that the List of 81 were sent to all of the ACUC planning committee for ACUC 2010.
I recall talking to Jon years ago, and he was mentioning how they would get suggestions by the boat load. I guess every company is different. I imagine Apple must get thousands a day, maybe less. But, how does a company request suggestions for their users. Some times I think there should be beta testing in perpetuity with local doctors (maybe five) contacting Jon weekly. How many of us find issues just by using it.
As far as which ones, to be honest, I haven't really been in "What features do we need mode" since a while back. I have seen users fall off the board after waiting so long.
How much money? I, personally, think AC is far too cheap. If it cost more, maybe we wouldn't be in the Pri-Med mode.