Steff:
No, I really can't think of any way to second guess ODS PDF. Too much goes into building a report row and too much goes into assembling those report rows into a "page image". The only time I ever had any success with calculating number of lines per page was when I used the LISTING destination and only the LISTING destination.
ODS PDF is not creating a report in a vacuum...First, PROC REPORT is building the output object, then that output object is sent forward to the destination, at which point style and/or customizing information is added as appropriate to the destination. So for example, the SAME PROC REPORT step could generate different results when sent to 2 different destinations, because the style/ font/ cellpadding/ etc information was different for the 2 destinations. An HTML report generated from PROC REPORT can be as wide as it needs to be, so as the output object is sent to the HTML destination, width controls have little impact, except for the explicit OUTPUTWIDTH or CELLWIDTH style attributes.
On the other hand, the PDF file is bound by physical margin limits (which are different from number of lines) -- a PDF file that has bigger margins will get fewer report lines per page than a PDF file that has smaller margins. Similarly, a PDF file using in a smaller font will be able to get more report lines per physical page than a PDF file which uses a larger font.
It sounds like your "house style" wants LISTING-like control in the world of ODS. The only way I know to get that kind of control -- and even then, I don't know that you have "line per page" type of control -- would be to look at the DATA step object interface (experiemental) to ODS.
http://support.sas.com/rnd/base/datastep/dsobject/
Or, you could work with Tech Support to see whether there's a way that more conventional techniques could be used to replicate your house style.
cynthia