So I was thinking there should be iron and gold buttons, perhaps even levers. The way they would work is the longer it's held down the greater the redstone power would stretch. This would make timing easier, down side is you have to hold the button. Though if this was a lever then that problem is not as bad. I know there are ways to accomplish this via redstone and the components we have now, but seeing that function in a button or lever sounds awesome.
Perhaps iron could require you to hold the button and gold would just increase in power until it's 15 then revert back down.
Anyways I doubt this idea will get much support and I do know that people like the challenge of redstone being part of the game.
Also maybe they could change gold/iron pressure plates to use this idea, I mean do people even use those any more, not for their intended purpose at least.