Thanks for following up with examples. I recognize the fact that you have a problem with the colors in the first shot. I personally would also be quite displeased with that outcome, although I bet plenty of people would find it perfectly acceptable. We all differ in our standards, but within that variation, I do understand where you're coming from.
I'd start by bypassing at least momentarily the complications added by the black-box nature of the corrections applied by tools like ColorPerfect and do this manually. It might help if you could upload a raw (uninverted, uncorrected) scan of a frame or a few frames so others can have a go at balancing them. At the very least this will demonstrate how much the digital part of the process affects the final outcome. At best it can show whether or not there's something odd going on with your film - but frankly, I don't expect so (although each film of course has its own peculiarities in how it responds to colors and light).
As to the sharpness - the second image is indeed a fuzzy mess. However, given that the grain also doesn't render particularly sharply, I hesitate to accept it has anything to do with the film. My guess is something went wrong with scanning, particularly focus. I don't use an LS9000 myself so I'm not familiar with its ins & outs, but I do know it's capable of far better results - as you yourself also demonstrate.
Of course, there's always the chance of a process problem; how was your film processed and are there any other signs of a processing issue?
Having had a quick look at your first image, here's an attempt to balance it out a little better (to my eye), but of course (1) I wasn't there and (2) I don't know what expectations you have of the end result, so perhaps you don't find this an improvement at all. Either way, it does show that a fairly subtle adjustment can get rid of e.g. the magenta bias in the trees bottom left.
As you can see, I did apply non-linear (i.e. crossover) corrections, but in my experience it's quite common for tools like ColorPerfect to do funny things to color curves, so I wouldn't jump to the conclusion of crossover in the actual negative.
Also, color-wise, the other examples you posted do look nice, but the first two are problematic because those 'golden hour' colors are always so extreme that even a gross deviation from normal can go unnoticed. I personally have doubts about the Ektar shot in particular looking at the hue of the sky in relation to the sunlit stonework; again, I wasn't there, but it seems like a rather implausible combination to me (it can still be pretty of course).
The quality of the light is of course a tricky thing to begin with; e.g. the photograph of your wife is balanced very warm, while in reality, the light in that shadow area must have tended very strongly towards blue. There is a hint of a green cast; a green/magenta issue is consistent with your first photo.
The culvert image looks fairly neutral, albeit with a slight cyan bias. I would print or digitally balance it a little more red.
What I'm saying mostly is that:
1: There are no absolutes in color photography. It's all very relative. This is particularly the case with color negative.
2: Each of us applies different criteria to the end result. I'd wager to say that much of the time, we are only partly aware of those requirements, which is at least part of the reason why we sometimes (I myself certainly) run into problems with certain images.
3: Digital editing is extremely flexible. And this is a blessing as well as a curse.
Sorry if this isn't entirely helpful, yet. I would be interested in seeing that 'raw' scan, but don't feel pressured into sharing it.