Re: Simple Solution
"So the US voters are blocked from directly and immediately forcing their elected representatives to vote a certain way on a specific issue. Fine, let's say they could do so instead."
No that is not what removing the current corrupt system for selecting committee members in congress based on seniority would do.
People run for congress on many issues. You do not elect multiple congress people, one per issue. You vote for one candidate and he or she decides which way to vote on when it comes up.
That is how democracy works in most countries. You vote for the candidate who most goes along with your wishes.
What you're stuck with in the USA is voting for a candidate who doesn't give a damn about you and your wishes because that candidate has years of seniority that guarantee him a seat on a committee from which he can do pork barrelling. Pork barrelling is getting funds unjustly sent back to his district or state, often as kickbacks in exchange for campaign contributions.
What doing away with the corrupt system for selecting committee members in congress would do is give all congress people a chance at getting on a committee.
It would restore democracy and allow voters to vote the best person into office rather than the person with the longest incumbency.