I think it is not good to be too hung up on denominations. They are just a fact of life, and I think only God can and will one way tear them down. We hear the shout of zealous
brothers protesting: Lord, Wilt thou then that we go and gather [the tares)?
But the Lord said, Nay; lest while ye gather up the tares, ye root up also the wheat with them.
If you try to do it by human effort, you will actually pull out the wheat with the tares, and cause collateral damage.
We are always happy for the walls of others to be torn down, how about our own?
Sometimes it is not even doctrinal matters, but length of skirts, Christmas, organ or guitar, pastors pay, vaczine, and other trifles.
Let it be the work of the Spirit, the only One who can bring us to the Unity in Christ.
I have been to many churches of various denominations. I have had bad church in many places, even there I always met a few starved hungry dear souls among a mass of nominal Christians, sticking it out for want of elsewhere to go. I have set under sound, but dead teaching. I have been in churches with whacky theology but great hospitality. I have seen churches great in prayer, great in outreach to the outcast, rich in sending out, great in song, but all may be lacking here or there.
I have seen beauty and freshness of the Spirit among conservative Russian Baptists founded by American Baptists in the 1920s, British Charismatic, Southafrican Pentecostal Brethren, German Baptists, A Chinese Church founded by Swiss Missionaries, a Hong Kong crowded home in the the Walled City, house groups and prayer retreats in Taiwan, and my most powerful eperience ever was in the Philippines back in 84, when a 5 feet tall pastor preached from Acts 8 where I had an open vision about the wrath of God.
All of them sort of belong to denominations, vary greatly in practise and emphasis and style, perhaps just because their founders were baptist or methodist or Lutheran missionaries from somewhere where people cared about the lost.
What I found is, though they do things wrong here and there, they may excel in other ways and virtues.
I can reject a lot of their baggage but also can learn a lot from them.
Actually the worst churches are those who say they got everything right and everyone else got it wrong. I love it when churches say, we are thankful for what we have but there is so much more we need to learn.
You may see them as walls, but they also can be like gemstones of differnt color and sparkle once Gods light shines on them.