Her weight sounds just perfect to me. Of course, I always go more by how their ribs feel than the breed standard, but she's right on breed standard.
My first Pyr, Cara, stayed right in the 92-98# range from about 2-12 yrs. She was from working/show stock and a very pretty & strong girl, so I think that she was a pretty good example. My second Pyr, Halley, we lost to bone cancer at a little past 3 yrs old and the most she ever weighed was around 80#. She was from very closely line-bred show stock. Our vet could never figure out why she was tiny & thin, he finally decided that it was just her build, then she got sick. She was very pretty and had a beautiful disposition, but was never big or strong physically.
Now Cassie (who is probably 3/4 Pyr and the rest is a mystery to us) is around 85# at 2 1/2 and she's very healthy so far (thank goodness!). Last, but certainly not least, Sammy is around 105-110# now and we have to watch to keep him from getting overweight b/c he really loves to eat, but he has joint problems so he doesn't need more heft to haul around. He's not a tall Pyr, but my sweet boy is solid & built like a tank.
I'm guessing that you'll see Jenny put on a few more pounds as she finishes maturing, but she'll probably be at her full weight around 3 to 3 1/2. Please give her a hug for me.