I have not had problems with child/parent disagreements

Yes, it's always possible to get around the problems. I only want these things to be automatic. I used to think bless should be automatic, but now I'm not so sure (it does provide a lot of flexibility). But calling a parent's destructor should definatly be automatic.

considered it adequate to have the abstract class die at runtime if a method gets called that should have been overridden by a concrete child

I think you genuinely have been lucky here, though lucky in a way that almost everyone else will also get lucky. Consider a child class that implements everything except one little-used method left unimplemented in the child that nobody notices for years, long after the orginal programmers of the parent and child classes have left. Since the checking is done when the method is called, nobody notices it. One day, somebody notices this obscure method and decides to use it. Oops, runtime error. Cracks appear in the earth's surface. The sun explodes. All die.

Most of my OO background comes from Java, which may not have the best object system, but is is very clean compared to C++.

Most of the things I consider broken in Perl's object system are being fixed in Perl6, along with a few other parts of the language that bug me (like parameter passing to subroutines).

----
I wanted to explore how Perl's closures can be manipulated, and ended up creating an object system by accident.
-- Schemer

Note: All code is untested, unless otherwise stated