This is a fascinating discussion and it's heading in an interesting direction, but I have something to say that's a bit off-topic, concerning Lobelia, whom Firefoot talked about in detail. I think through this character, Tolkien was trying to underline the difference between the evil and the dislikeable. In our day to day mundane world we seldom meet evil incarnate, rather these annoying pesky individuals, which our imagination turns into monsters come to torture us.
People often act this way, applying the attribute of 'bad' to one whom they dislike. Frodo's higher wisdom and his deeper knowledge of evil at the end of his quest made him more tolerant to Lobelia's ways.
To get more on topic: I agree with Firefoot that beyond Lobelia's annoying surface lies the traditional feminine creature, protective and caring towards her family and faithful towards those whom she loved. One can argue she's even got a bit of Eowyn in her when she attacks the ruffians with her umbrella!