It seems to me that it is an interface wart that we have two dialog
boxes in succession when printing checks.  First we have a dialog
containing Gnucash-specific items, then the system Print dialog comes
up. Looking into it, I think it is possible to eliminate the first,
Gnucash-specific one, by inferring some items, and turning the others
into preferences.

Specifically, the Check and Date Format items can be turned into
preferences -- hopefully, people are not regularly printing checks in
different formats; if so, this could be specified per account.

The Check Position & Address info are specific to each check, but they
both can be inferred.  

Check Position can be inferred from the check #,
as long as the check format knows how many checks per page, and an
initial check # that appears at the top of a page. (This initial check # value would have to be added to the check-format format, .chk)  There are various corner-cases where this might fail, and so it would be good to figure out a sensible interface for it to be changed in specific cases -- but there's no need to prompt the user for this information every time.

Address can be inferred from the Payee by looking into the Vendor list, as was originally the case when the Address feature was added.  To do this will require some re-architecting of the relationship between check printing and the business objects; I'm thinking that the address would simply be blank if the payee didn't match the payee value for a vendor entry.

This should probably wait until the multiple check printing feature (bug# 621016 ) is merged.