^^^
Indeed.
Kira was no where near as strong as she became when Vitiate possessed her temporarily. I think that Vitiate pushed her to her peak potential, surpassed her midichlorian dictation or something.
Heck, Vitiate was disappointed by Kira's strength. He declared her "weak."
This doesn't means that Kira is not strong in the Force but that she qualifies as "weak" for someone as powerful as Vitiate. Well, of-course, Vitiate's standards are ridiculously high.