My preference lies in making the policies a lot stricter, and actively verifying current delegations. I see a lot of ASN's requested just for fun with no real motive behind it.
I think this is already the case, at least with ARIN... I have definitely had to thoroughly justify each and every ASN I have received from them in the last 2 years (total of 6). In fact, I think it was actually harder to get an ASN than to get v4 prefixes in that same time period. I think it is not unreasonable to work towards a policy of 1 AS gets at least one IPv6 prefix and no AS can originate more than one prefix longer than /32 (/33-/64). I think that combined with the current policies towards ASN issuance is probably reasonable routing table size. Owen -- If it wasn't crypto-signed, it probably didn't come from me.