True, 'God' is not adequately described as being 'a Jew'. But is it not apostasy on its face to remove all Jewish heritage from Christianity? My heart looks toward Jerusalem, and I'm not ashamed.
Not at all. Jewish customs (what you refer to as 'Jewish heritage') are not part of the gospel of grace, and falling away from Christ can only be a fall from grace, not from any peripherals like Jewish traditions or customs.
I would suggest reading Paul's epistle to the Galatians. In it, he argues that the Gentiles are not to be held to the Law any more than post-Resurrection Jewish Christians are. For example, Peter regularly ate with Gentiles according to Galatians 2, which is contrary to Jewish traditions--one is not even to set foot in the home of a Gentile if one is Jewish.
Jewish heritage? Well, I think many of us Christians learn a little something about that most Sundays. :-)
It's hard to explain and I probably won't do so very well in this meager sentence, but I consider Judaism much closer to the origin of my faith than, say, Catholicism.