Going back in time, it was never encouraged for people to marry outside their faith and this covered most christian religions in the United States. Catholics basically married catholics and protestants basically married protestants.
And depending on his views of the Sabbath, you will probably get the tug of war on Sundays. And after years of this struggle, will your love for him and desire to avoid the hassle cause you to reduce your activation.
Until you can believe someone else's beliefs are reasonable, you will not be able to treat them with the respect they deserve.
And you seem like a good person. I think there's a chance you two can find a way to agree on a lifestyle and values.