If he does have the angora wool, he will need more protein to grow that wool. If they don't get the right protein, they will take it from the body and loose weight. 16% can be good for a pet, especially if he will be neutered. This can mean that he will have to be on an alfalfa pellet. You can try with a timothy pellet, but it might not be suitable. It can take a few months for any affects to become apparent. Chewing the wool is a sign of problems.
When it give veggies if up to you. If he is doing well with the diet of pellets and hay and settling in well, then you can start giving small amounts. I started giving Felix veggies when he about about 3 months old and he has done fine. Some rabbits are more sensitive though, so when to start varies from rabbit to rabbit. You do want to avoid too much change too quickly.
The larger breeds do take longer to grow, but they do grow quickly in the first few months. Felix was about 4 pounds at 10 weeks, 7 pounds at 4 months and 8 pounds at 7 months. I hope he won't grow too much more. He is a Rhinelander, so should not be more than about 9.5 pounds.
