And maybe the only one he has. We see it again in "Nightingale", when he loses someone under his command.
True about Bryd, but Tom was on Earth and not in constant danger. So it's a bit more of a toss up with him.
Maybe... but remember, Voyager was one ship against an entire quadrant. The odds of her getting home were remote at best. Harry had to know that on some level.
It's hard to say... basically, what happened here was a vendetta against the actor, carried out by showrunners of dubious competence. It did not follow the rules that had been set by the previous three series and also Voyager itself, i.e. that crew could be promoted without changing jobs. But it still happened and it was defended in canon, so we really have no way of knowing whether Harry expected a rank boost or not.
Remember, there was a totally legitimate reason for Harry to just accept the new status quo, and it had nothing to do with improvements in his life or problems in Byrd's and Paris's... he was given the following warning...
"Well, you may be able to change reality again, but there's no way to predict how it would change. You could end up at any point in the space-time continuum. You might return to your original reality, or you might find yourself a billion years in the future. Or at some time before sentient life even existed on your planet."
Given that there was a good change his attempt to change things back would fail, I can seriously see him having strong second thoughts.