| Quote #4
Or softly lightens o'er her face; (line 10)
Byron has said that the woman's whole "aspect" is beautiful, but now he's trying to put his finger on exactly what makes her facial expression so gorgeous.
| Quote #5
And on that cheek, and o'er that brow, (line 13)
Now Byron's attempting to break down her beauty, one piece at a time, in order to understand it. It's like he's dissecting her beauty.
| Quote #6
The smiles that win, the tints that glow, (line 15)
The woman's smiles are "win[ning]," and apparently she blushes a lot – is he trying to suggest that she's a bit of a flirt?