Turret height is fine, it just looks disproportionately tall because it's not a particularly long turret like you see with most western tanks. The gun is small, though.
I'm not aware of a modern tank with enough slope on its main armor to deflect a modern long-rod-penetrator. You need hilariously high amounts of angling (we're talking 80+ degrees from vertical) to do that, as modern penetrators will actually dig in when encountering a slope.