i can't think of one example where I would choose a curious newbie over someone with years of experience... [...]
Just to be ornery: Product Testing
Often you need people who have had no exposure to your product, so you can learn what trips them up. Experienced people are, well, experienced, and less likely to show you what a raw new user might encounter.
That's why I recommend surveying your new employees for their insights at the 3 month, 6 month, and one year points on the job. Ask them to list all the dumb stuff they had to figure out on their own that the experienced employees forgot and now take for granted. If you don't capture it, the moment will be lost forever, and the newbies will become experienced and won't remember those hard-won insights that they will soon take for granted.
Here is an example related to woodturning:
When I started woodturning, I noticed that the shavings coming off the turning can be hot from the friction of bevel rubbing and cutting the wood. I felt it, understood what it was, noted it as a scientific curiosity, and moved on.
I have been to a bunch of woodturning club meetings, taken a few classes, read a lot of books, and even found a few web pages/videos on woodturning, but nobody has ever said anything about it. Not once. I asked around, and everybody knows about it, but nobody ever mentioned to me, despite plenty of opportunities. Some people told me that they apply tape to the back of their hands (or wear gloves, the horror!) because it bothers them.
Everybody seems to know about it, but they take it for granted. Nobody seems to mention it to new woodturners.