I figured preventing the (not impossible, however unlikely) case of
only org-outline-regexp being unbound was cleaner than just
declaring the variable.
Thanks for your contribution! To fix the warning for org-outline-regexp, a simple (defvar ..) should be fine. Since I'm going to fix this anyway, I'll go ahead and fix this one.
I figured preventing the (not impossible, however unlikely) case of only org-outline-regexp being unbound was cleaner than just declaring the variable.