I've biked with a hood a few times and found them annoying as the hood (1) would blow back off of my head and (2) wouldn't turn when I rotated my head so I was just looking into the side of it. I currently use a hat to keep the rain off of my glasses.

For anyone interested in other options, I think the following type of sun/bug hats would keep water from running down the neck. Since they are attached to your head they should solve the vision issues and you can get some non-bike specific use out them too.

Outdoor Research Sun Runner Cap

ExOfficio BugsAway Cap Hat

Showers Pass also makes this helmet cover with a rain guard in the back
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