My idea was to draw a cross into the heart - on a single line, as the cross being united with heart
So, maybe my first entry (
#27) doesn't express very clear that thought - so I've made some variations on that:
#54 - bolder color on heart, so the cross is more obvious
#55 - the cross is no the same line with heart's outline, but more prominent
#56 - added outline to cross
#57 - same as #56, only with bolder outlines