I've never seen anyone actually using RtConfig output for anything
else then destilling prefix/aspath lists from them in order to use
those in own generator tools. Given my own very basic and short
playing with RtConfig, I can somewhat understand why.
It would make countless lives much easier if it were possible to submit
a query to the db that gives back the desired output rather than having
to use these very complex tools.
Not a huge ISP but I certainly build my access list and route-maps (and
the equivalent Procket policy stuff) using RtConfig with no other magic
involved. In my previous job at one of Australia's tier ones we did it
that way too. See AS7575 (current policy) and/or AS2764 (previous one)
for outrageous aut-num objects. I don't use inet-rtr objects though.
Personally I don't think driving RtConfig is all that difficult.