Dear brother Kev,
My personal opinion:
If you believe ABC falls short of the mark, and permissible only under the principle of oikonomia, you should have no problem being in the Catholic communion.
ABC is intrinsically wrong since it goes against God’s Natural Law. Oikonomia might be applied on a case by case basis (indeed, such merely occasional application is an inherent feature of oikonomia). Oikonomia does not change the Law of God, nor does oikonomia make something normative. It merely mitigates, under particilar circumstances, the normal punishment associated with breaking the Law of God. For example, in the OT, certain sins deserved the temporal punishment of death. But if circumstances beyond a person’s control caused one to commit the sin, such as lack of knowledge of the law, or accidentally, the punishment is mitigated and the death sentence normally given was not meted out.
Part of the problem is that certain Orthodox think that oikonomia permits the Church to change Divine Law (Latin Catholics who misunderstand oikonomia in a similar manner think that the Eastern/Oriental practice of oikonomia is equivalent to “permission to sin”). So many Orthodox think that ABC is now normative and no longer falls short of the mark. That idea is foreign to patristic, Catholic teaching.
However, to repeat, if you believe ABC falls short of the mark, recognizing that before the 1930’s, every Church opposed ABC, and agree that oikonomia may be applied only on a case-by-case basis, and that ABC can never be normative, you should have no problem joining the Catholic communion.
Again, that is my personal opinion.
Blessings,
Marduk