Current test failures

Here is a non-exhaustive list of the test failures to fix.
* [ ] `test_crossinheritance.py::TestCROSSINHERITANCE::test23_const_byvalue_return`, `test_crossinheritance.py::TestCROSSINHERITANCE::test28_cross_deep` -- the CreateConverter seems to be going on the wrong code path -- @sudo-panda 