I think that in some cases with the media the way it is today that there is no way to find an impartial jury. In these cases it would be better off for all the parties involved to be involved with a judge that is getting paid to be impartial and knows the laws.
In general, I think that the right to a trial by jury should be upheld, but in the cases of cases extremely relevant to national security, like terrorism or treason, I could see not having a jury. This may seem like a violation of rights, but right now, people accused of these crimes are just held without any sort of trial, so at least now they'll get one. Given the amount of outrage in the population, a judge would be more likely to judge things fairly than a jury of average people anyway.
If we just pretend the Constitution isn't there for one thing guess what. We can do it for everything and the Constitution becomes as useful as toilet paper.
"Paying" someone to be impartial isn't going to work because of human error. It's better to have a jury and more importantly a good lawyer who will vet any biased jurors.
I do not think that the right to trial by jury should be limited under any circumstances because it is the foundation of our justice system, being guaranteed by the U.S. Constitution. Giving everyone accused of a crime the right to a jury trial is what gives our democracy and our legal system credibility and legitimacy.
The Bill of Rights asserts criminals have a right to a speedy trial and a trial with a jury of our peers. All criminal cases should have a jury trial. There can be impartial jurors found in any case if the proper jurisdiction is found. Some cases may have to go out of state, but there will always be at least 12 people who haven't heard of a particular case somewhere.