Both Islam and Judaism deny Christ, so I am not sure how the differences could actually be handled over time with a husband of the Christian faith. Same goes for New Age, or what I have come to understand is marked as 'Spiritual' on this site. Core beliefs matter. Being unequally yoked does have consequences.
The idea of differences in religion is not deep enough, what should be discussed is the idea of beliefs of the heart. What does someone truly believe when it comes to family, relationships outside the home, the world in general.
A family that is already established based on the beliefs of the 'family' risks being changed by the beliefs of someone coming in. A husband may think he can deal with that difference but the thing that may need to be consider is how will that difference effect the other members of the family's belief?
The method of morality most be defined within a family, is it from an external absolute source, or is internal based on what society, or each individual dictates? I know from the statement you made about the three man made religions morality is not as much an issue as it would be for someone outside those beliefs.
In any event, even though I don't think mixing of religious diversity within families is a good thing for some, all depends on the family structure and what they are willing to allow.
However, I think plural families need all the help they can get from the community of poly believers and so accepting poly families outside of religion is beneficial to all.
I have met and encountered many Muslims who reject and deny Jesus Christ, and who are willing to murder me if I tell them that they are wrong about their Issa and that their prphet Muhammed was a false prophet. I don't respect Muslims as their belefs is idolatry, and Idolaters won't inherit the kingdom of God.
The deity of Christ is according to the Bible. The Quran reject and deny The deity of Christ.
The Son of God is according to the Bible. The Quran is against The Son of God.
So, yes, it is is true that Muslims deny and reject Jesus Christ.
As a Christian man I am commanded to speak and preach the truth about Jesus Christ which is according to the Bible, no matter the costs. I am willing to pay the costs for believing on The Lord Jesus Christ.
Isa within The Quran is not the same as Jesus Christ within The Bible. Have this in mind.
Get to know Jesus Christ within the The Bible.
Read and Study the Bible from Genesis to Revelation, and you will see, recognize, know and understand that The Bible is much different than the Quran. Awake to righteousness and sin not. Use common sense and your own conscience while reading and studying the Bible from Genesis to Revelation.
I want to clarify a misconception. Islam does not reject Jesus. Islam accepts Jesus as a mighty Prophet of God, born of immaculate conception. It is Judaism that rejects Jesus all together as being a true Prophet of God. The Bible calls Jesus a Prophet of God, Islam accepts and confirms this. Islam accepts all of the Prophets of the Bible including Jesus. Muslims are taught to love and accept Jesus. Muhammad taught that Muslims should live in peace and harmony with Jews and Christians if they don't attack them physically or drive them out of their homes.