As I see it...
To Catholicism there's only one real difference between the two sides that can't be explained away: what I call the scope of the Pope. Is his office divinely instituted to govern the whole church and teach for the church on faith and morals? Both sides believe the church is infallible; papal infallibility is a subset of church infallibility. Both sides believe the episcopate is divinely instituted (the bishops are successors to the apostles). But is the Pope's office, Bishop of Rome, just a man-made application for that divinely instituted episcopate, like the Bishop of Scranton or as the Orthodox believe about all their patriarchates? The last is what I think Orthodoxy teaches. (Orthodoxy doesn't per se hate the Pope! It venerates pre-schism Pope saints as Popes. As Ware wrote, in Orthodoxy a special place belongs to the Pope.)
Catholicism says sacramentally the two sides are the same but with that big difference, an inch wide but infinitely deep, they are on parallel tracks. Union is zero-sum; one side has to cave on that Pope issue. Since both sides claim to be the one true church, of course strict Orthodox rail against ecumenism.
The rest of it's either explainable (the filioque, purgatory*) or discipline not doctrine. Before the mid-1900s, being against contraception wasn't 'just a Catholic thing'; it was generally Christian. About it, most Orthodox now sound like mainline Protestants did in the '50s and evangelicals do now: plausible, cautious and conservative (for married couples only and only for good reasons; ask your pastor). Rome holds the line.
Beyond that? I'll stick to something not controversial here. I think we can agree that Rome made a huge mistake by trying to modernize its services in the '60s, making its liturgy more Protestant, less like the Orthodox. The professional theologians' claims, that the Second Vatican Council moved Rome closer to you, are, obvious to any visitor to each church, false. The older Mass (Latin Mass, Tridentine Mass) is obviously more like the Orthodox Liturgy. It's the preferred rite for Western Rite Orthodox! (That and orthodoxified versions of Anglican services. At first, the late 1800s, it was the only Western service the post-schism Orthodox approved for use.)
I think the Roman Rite in antiquity was probably simpler and duller than the '50s Mass. Around 1000 there was a reform in the Roman Rite in which much was copied from the more flowery Gallican Rite, which in turn was influenced by Eastern rites. So that and the many beliefs in common (priest, sacrifice made presence, Real Presence in the holy Gifts/Communion) explain the 'family resemblance' between '50s Catholicism and Orthodoxy. (Why a number of Roman Rite Catholics have taken refuge in Eastern Catholic churches.)
Orthodoxy to its lasting credit has kept alive a grassroots folk religion naturally resistant to wholesale changes ordered from the top, like the 'Reformation' or Vatican II. Historically Western Catholicism worked much like that too. (The Pope was actually a distant figure people didn't much think about.) Something the West should relearn from you.
*I'm not a credentialed theologian but 'from the Father through the Son', and prayer for the dead supposes an intermediate state. Orthodox enthusiastically pray for the dead. Purgatorial fire's not doctrine.