Not exactly sure what you are getting at... but if you are getting the idea that Christians are saying that non-Jewish Christian practice has a valid place... some in fact do. I believe it does. It carries a witness about the purposes and character and desires of God. It is a love story writ large in history. To lose memory of it would impoverish the world.
Spiritual “technicalities” — if we can call it that — are what Christians like I proclaim that the coming of Jesus into the world was and is about. We affirm that no man is fit for heaven in this world, and that God has purposed to get whoever is willing into heaven. Worship in this world can furnish an echo of heaven, but it’s in a creation that is “subject to frustration.” Christians affirm that God stooped to take on bodily form, waiving many of His privileges while in that mode, in order to visibly suffer the burden of human sin. You don’t have to know that immediately in order to be able to accept the salvation, but if you do accept it, God will sooner or later show you how He did it. There are going to be a lot of saved Jews who will see the suffering on the Cross for them and they’ll say God are you meshugah? And God will say yes, I was meshugah for you.
“Meshuga (crazy)” You sound like a chassid.... we already have a tradition of being crazy for G-d. It dates back to the Tabernacle. (I believe this predates Jesus by about 800 years)
http://www.sichosinenglish.org/books/basi-legani/08.htm
It’s a little “yeshivish” (ie, in a mix of English, Yiddish, and transliterated Hebrew) but you may find it interesting.