Are these bare prints?

Not surprising for metal but surprising in the context of a high quality artwork print can take quite a bit of abuse.

Chromaluxe has semi gloss and matte finishes. It’s probably just that your particular lab doesn’t carry them but others do.

Direct to dibond is probably a UV printer.

In terms of quality of your three options, id rank them (1) paper print mounted on dibond, (2) chromaluxe and (3) direct UV dibond.

Paper is definitely the best quality but chromaluxe can still look very good too. UV printing is not as high quality but may be good enough for you. If your lab is local go in and look at samples.

Stay away from brushed metal prints unless you’ve seen it before in person. It’s a very niche look and doesn’t work for many images imo.

The reason I ask is because I am thinking of making some large prints, like 40x60 or larger, but am not sure what to do once I get them.

I think this explains the popularity of ready to hang art like metal prints which don’t need a frame. Metal is surprisingly robust and although pricy, aren’t as pricy as having a paper print framed. If it was smaller, I’d frame it myself but a 40x60 isn’t something I’d attempt.

Yeah every couple years I buy new hard drives.

I have about a dozen that are about 10-20 years old. It’s getting hard to find a use for them, but so far I just use them as a 5th level backup, write once. I also destroyed a bunch that were too small.

Use internal drives with a dock and store cold. Saves the hassle of dealing with a bunch of cases and power adapters.

For fully on backup all the time use a versioned backup like time machine or a cloud service.

I’d look at products like topaz photo ai. It should do things like color correction, brightness and sharpening. I don’t think it does dusts spot / scratches although that’s probably on the feature list to add. You could also use a two step process with another program for dust spots.

If topaz or similar ai product doesn’t do exactly what you want, I’d start scanning but wait a year or two to process as these programs are rapidly improving.