What is a good choice of letters for serial numbers?

When creating serial numbers, one could use only numbers, 0-9. This causes serial numbers to be quite long. To save space, one could also user letters A-Z, resulting in shorter numbers, by a factor of 1.56 (log 36 / log 10). But this can cause trouble reading those serial numbers, since 0 and O are quite similar. Also l and 1, and mayby I and 1, or even J and 1.

So a first approximation seems to be to use the digits 0123456789ABCDEFGHKMNPQRSTUVWXYZ for serial numbers. That is 32 digits and hence serial numbers are still 1.51 times shorter than in base-10.

Is there any well-known best practice for issuing serial numbers?