The important thing to consider is that all opinions will vary, even within this forum. Some of that is because people are uninformed, but other times, it's just because there is more than one "accurate" way to do things.
If you have access to a good pellet, that can make balancing the diet much easier on you. Alfalfa-based pellets are most common and, in my opinion, are the best choice. For a pet, I would look for about 15-16% protein and about 1.5% fat, as a general rule. A Lionhead should be getting about 1/4-1/2 cup daily.
Then, it is great to also add a fresh grass hay (timothy, oat, mixed grass, etc.). Give your rabbit as much hay as he will clean up in 24 hours. That way, it is always available to him.
Those two key foods should round out the diet pretty well, but you may also choose to feed bananas, dandelion greens, clover, grass, etc. as treats or supplements too.