Has strength of character been presented positively in The Crucible?
I'm finding it difficult to say, because to me, the only strong character who does not die is Elizabeth...and yet she lied and so demonstrated a flawed character. Alternatively, Abigail was also a strong character, but she definitely was not seen positively. So I don't know how I would write about this question. Proctor; sure...in dying he demonstrated strength and maintained his dignity but is this portrayed positively?
I'm lost as to what arguments I could use for and against here.
Your thoughts and arguments are good. The term 'positively' obviously has a personal element to it - it could be interpreted in several ways. Here are some things to think about. Elizabeth did lie, but she was doing it to try and save Proctor - would this still be considered a character flaw? Proctor did die in the end, but he died as you said maintaining his dignity, and Elizabeth tells Hale that he finally has his goodness, so maybe his character is positive even though the results of his character are not. In addition, Francis Nurse, Rebecca Nurse, and Giles Corey all show strength of character even though the result of their character is death. Remember, as Puritans, they would have believed that they would be rewarded by going to Heaven for doing the right thing when they died.
I think Proctor would be a fine choice. Yes, he dies. However, he redeems himself through his death. He is one of the only characters to speak the absolute truth. He calls Parris out as a greedy minister. He calls the court out for seeking vengeance. Finally, he calls Abigail out for her false accusations.
Throughout the play his major flaw was that he was willing to keep quiet because of his guilt for having the affair with Abigail. However, when he sees that it could very well cost Elizabeth her life, he finally tells the truth. Despite the pressure to falsely confess in order to save his life, ultimately Proctor refuses, wanting to keep his good name which has been redeemed and which he preserves through his death.
Another character who might work is Hale. He is chiefly responsible for the mass hysteria (look at the leading questions he asks Tituba which lead to the accusations). Yet when he witnesses Elizabeth's arrrest, he starts to question the truth, which is something Danforth and the judges don't. By the end he has withdrawn from the court in an attempt to show how unjust they are.