Paul is removing the dust in photoshop (there is no auto-filter in Vuescan to do this). I'd echo the suggestion of doing this manually though - auto settings always end in compromise IMO.
The scans are really clipped at both ends Paul leaving large black shadow tones and featureless highlights.
This could be an issue with your vuescan settings, although equally may just be your monitor calibration - I suspect it's the former though as other scans you've posted haven't looked that way. They are also very soft.
I dont think there is any shame in making adjustments in photoshop to get your tonal range right. I find that Vuescan is great for getting a good scan with lots of detail - but only as an initial stage to be further realised in editing software.
My method with Vuescan is to scan at whatever DPI you like, but make sure 16 bit is selected (if you are in greyscale that is). I do have the sharpen filter selected. Once I've run the preview, I select the frame I want in the preview pane, then click on the scan pane and press ctrl+E (or in mac cmd+E) to get a large preview. Selecting the colour options, I use the levels sliders in the bottom left hand histogram to ensure the dark and light points are just outside the clip point, then I set the lightness value to what suits the image best - usually .75 for my films.
Next I press the scan button. Once this is done, I double check the histogram clip points again to make sure the software hasn't overridden my settings, then save.
Next I open in photoshop. Firstly, I apply USM settings at between 75 at 0.75 radius to 150 at 1.5 radius depending on the image resolution. Next I use the auto spot tool to get rid of dust and artefacts. Next I open a levels layer and set the dark and light points (which are invariable slightly flatter than the histogram in vuescan suggest)- if you hold down the alt key whilst doing this, you'll get a clear indication of when you have gone too far. Next a curves layer to sort out contrast. then feathered selections and curves to sort out any dodging/ burning required.
I then like to flatten and convert the file to RGB 8-bit. I create a colour balance layer and add tones that way as you can add individual tones to highs mids and shadows - you can be much more subtle than using preset tones, which never quite work IMO and it is much easier than duotoning also i think. Finally, I resize for web, but then re-sharpen. My method at this stage is to apply small amounts of sharpening repeatedly until it looks correct - about 30 at 0.3 radius - it usually takes me about three applications depending on the size of the original scan.
that's it. Hope I'm not teaching you to suck eggs, but I found it really helpful looking at other's workflows before I settled on my own. Mind you, I only scan for web display - I never do digital prints from my scanned negs.
As for the lakes - here are a few from the past 10 years:
