Sure, some Catholics are ignorant and/or jerks, including about the Orthodox, maybe not up to date about giving born Orthodox the benefit of the doubt, or, allowable, believing something like Leonard Feeney about them. But we're discussing talking someone out of leaving the Catholic Church. Is the objectionable thing to you a nasty triumphalism or simply Catholicism's true-church claim vs. Orthodoxy's?
Is Orthodox practice reconcilable with Catholic doctrine or are Orthodox-style Greek Catholics fakes, Oreos? Here the two sides disagree. If you agree with the Orthodox and OicwRs, you're no longer really Catholic. I'm sorry but wish you well and hope you find what you're looking for.
Thomism is almost synonymous with Catholicism but just like Catholics don't have to be ultramontane or Roman Rite, they don't have to be Thomists. Palamas may have been nastily anti-Catholic for all I know but born Orthodox get the benefit of the doubt. I've never known a Slavic Greek Catholic who knew or cared who he was; I think the very Orthodox-style Melkite Church venerates him.
Orthodox-style Greek Catholics: Melkites, Russian Catholics (born Roman Riters), many of the few born Roman Riters in the Ruthenian and Ukrainian Catholic churches, and Greek Catholic priests trained in Rome. The rest, the ethnic Ukrainians and Ruthenians, are essentially nice ethnic cultural-conservative Roman Riters with a different Mass. (The old po-nashomu inter-ritual mix but now with a hardened Catholic identity since the American schisms and Communism in Europe.)
I'm against any program to latinize Eastern Christians, because their practice is already Catholic. That said, as an outsider it seems to me that, although the Greeks have never hellenized ACROD, in recent decades as our ex-Protestant host American culture's become more anti-Catholic, the reverse of the Greek Catholics' self-latinization has happened in ACROD. That and Orthodox anti-Westernism feed off each other. ACROD's now a bit ashamed of its Catholic heritage; it wasn't before, even though it always was mad at the Catholics, understandably. So a church created to preserve po-nashomu religion 'as is' (they wanted things to stay the same, very conservative, very Slavic) ended up no longer being that but a kind of ersatz Greek Orthodoxy with different music, rather like the Metropolia/OCA Ruthenians, most American Russian Orthodox, are now ersatz Russians. Both are now self-consciously Orthodox just like the Ukrainian and Ruthenian Catholics are now self-consciously Catholic and happily self-latinized.
Right, the departing Greek Catholic parishes, in both the Toth and Chornock splits, kept those words in their names partly for the po-nashomu reason – in the old country, Greek Catholic was their only faith, and to them at the time, it didn't necessarily mean under Rome; they didn't care that much about that – and partly for the legal reason that it helped when they were taking and keeping their property from the Catholic Church. Not really because of Orthodoxy's boast of being the real Catholic Church, nor because they really missed the Catholic Church. The term is still in ACROD's official name as far as I know, the American Carpatho-Russian Orthodox Greek Catholic Diocese of America or of the USA. Likewise, for decades, from the Toth split until autocephaly in 1970, the American Russian Orthodox' official name was the Russian Orthodox Greek Catholic Church of America or of the USA. Because most American Russian Orthodox are originally po-nashomu Slavish, not from Russia.