The alfalfa “cutoff” is around 6 months, so now sounds like a good time to start very gradually transitioning your bun to a timothy-based diet.
The vet saying she’s healthy is good, since it implies that she’s at a good weight (rabbit savvy vet, I assume).
Now in terms of pellets, those are best fed by weight – follow the directions on the bag, and when you start weaning her off the baby ones, simply mix with adult pellets to avoid shocking the bun’s tummy (you can start with a small part adult and work your way to all adult).
In terms of veggies, there’s great info in the Bunny Info tab at the top of this page – it tells you bunny safe veg and suggested quantities per body weight.
Finally the hay – adult buns can have good quality timothy, orchard grass, or even oat hay. Try a few different kinds and brands – buns can often be picky and have very pronounced tastes. You will eventually find a hay she eats that’s not alfalfa, and you can always encourage her to eat more of it by using hay toppers (dried bunny save herbs and flowers) from time to time, or putting only timothy in her litter box area to encourage snacking while toileting, etc. 