People will come up with many ways to generate profane language. See guids/uuids for example, or l33tsp34k. A major change to hypothetically prevent a single case seems unbalanced.
It was important enough that Douglas Crockford entirely removed the letter U from his system except as one of several choices for a check digit. I opted for the same tradeoff for Base32H; if anything, keeping U/u as a separate digit would be the major change. V and U look close enough together (more so than I and L, especially in real-world conditions where legibility is poor) that it didn't seem unreasonable for the latter to be an alias of the former.