I disagree on multiple accounts.
Despite her popularity, Joan of Arc was more Sith like than anything. She was driven by her hatred of the English
Well, on her trail she said: "Of the love or hatred God has for the English, I know nothing, but I do know that they will all be thrown out of France, except those who die there." That doesn't answer if she hated the English. But she beliefed that her emotions were irrelevant, because God wanted the English out of France. Following what you percive as the "Will of the Force", no matter your emotions, is a Jedi-like attitude.
as well as her belief in the divine right to rule of her King, both of these motivations are Sith rather than Jedi.
Sith do not believe in some divine right to rule, except the right to rule for the strong. These are opposites:
divine right to rule for the king: no matter how weak the king is, he has the right to rule
right to rule for the strong: if a ruler is weak, he needs to be overthrown, no matter what rights he claims
Further more she frequently hallucinated, due to her self enforced starvation, which is definately unJedi in nature.
Jedi and Sith both have Force visions. Jedi sometimes try to trigger visions through meditations. I don't know if some Jedi meditations include fasting, but I don't think it would be against the Jedi ways if they did.
I know one Sith (Lord Cylpho) who starved himself to bring himself close to death. He though that when death closes in, he would see visions of the future. I doubt that Joan Darc fasted to bring herself close to death, though.
By the way, she started fasting after her visions started.
(While visions and hallucinations are not the same, they are pretty hard to distinguish. I'm pretty sure that there are many people in the Star Wars universe, people like Tharan Cedrax or Admiral Motti, who woult call Force visions hallucinations.)
All in all, she doesn't seem more Sith like than Jedi like. She seems more like a Jedi who might be in danger of falling to the Dark Side (or maybe a fallen Jedi, but not a Sith).