。
It's not so much that she's kind — she's genuinely warm.
Literal
She [topic-は] kind [rather than-というよりも] [rather-むしろ] gentle.
A deliberate contrast between two related but distinct virtues. 親切 implies actively considerate or helpful — doing things for others, going out of one's way — while 優しい denotes a softer, inherent gentleness of disposition, the warmth someone simply emanates. The pattern ~というよりもむしろ is a refining maneuver: 'it's not quite X, but rather more like Y.' Useful when you want to correct a near-miss characterization without rejecting it outright. The doubled emphasis from よりも and むしろ together makes the speaker's reframing feel deliberate, as if mulling over the right word and landing on it.