I like this, though I agree with others that the minimally-confused U & V, would be better traded for the oft-confused 1, I & l.
One slight additional issue not so far mentioned is what of the case of needing to encode one of many now "NSFW numbers", such as the trigger-warning (!) decimal 739787225?
Yeah, that's a hard-to-address problem with any number system like this (for example, most other base-32 systems have this problem, as do Base64 and pretty much everything else using the full alphanumeric range). Aliasing U and V is an attempt to do the same for a different case (addressing e.g. decimal numbers 519571 and 421594).
If I didn't have as strong of a want for a power-of-2 radix I'd have aliased G/g to 6 (and re-aliased L/l to 1) to further address this. Maybe even aliased B/b to 8, since sometimes that's a source of readability issues (and it further mitigates 11594129).
One slight additional issue not so far mentioned is what of the case of needing to encode one of many now "NSFW numbers", such as the trigger-warning (!) decimal 739787225?