If nothing else, it's probably time we give OpenERP another look just to get an idea of how problems are being handled there. Pointers to useful reading would be welcome, if you've got any.
The best introduction is probably Integrate You Logistic Processes with OpenERP, a free ebook written by OpenERP S.A. themselves[1]. It's slightly outdated, since it was published in 2011 and meanwhile version 7.0 has been released, but the changes to the stock area where limited (except for the UI).
We have a demo instance for version 7.0 [2], but it's in Portuguese (though you can change the language). OpenERP S.A. offers a free trial.
