Moderation and variety is the key. Rabbits are natural foragers, so make eating a game to him and it should help with the binging. Here's are some tips I use with my buns to make sure they stay healthy.
Rabbits can quickly learn to adapt to a schedule, so try not to create one. If they know pellets come at a certain time, they can and will often refrain from eating anything else because they know something else is coming soon. My Anya was that way and was becoming quite a chubster.
Pellets - about 1/4 cup for every 5 lbs. I split everyone's portion throughout the day. I use a ceramic bowl, treat ball, dig box or randomly place little piles in different bunny favorite spots. My buns now don't have much interest in pellets and I end up throwing about half of the previous days portions away.
Veggies - I used clothes pins and random bunch a few veggies together and clip them to...anything really. Any where your bunnies can access. You can use a piece of string between 2 chairs and clips veggies to that also. I used to put it in a pile on a towel and they would munch, but they go through the veggies in the morning and look for more at night. So I had to switch it up.
Hay - They only food they have access to 24/7 is hay. Timothy, orchard and oat hays are used in their litter boxes, brown paper with hole punched into it, hay managers and toilet paper rolls filled with hay. Hay is the only aspect where overload is ok. Alfalfa is the only hay that should not be given to adult bunnies unless you are planning on breeding. It can be given on occasion, but I would avoid if possible.
Treats - It's super cute, especially when they learn to beg for it, but you wouldn't give your children ice cream every day right? Carrots are considered a treat to rabbits and should not be given freely. In this aspect, I just try to relate. I can have a dessert, but once or twice a week. Its the same thing. For example, if you do decide to give your rabbit a carrot, cut it up in a few pieces and have him look for it. That way he gets a treat, but he has to work for it. Mine feel that treats that are found, taste way better than treat handed out even though it the same thing. They do thing super happy eye squint thing when they find the treats I've hidden. It's this weird look of satisfaction..heard to explain, but if you see it, you know.
Exercise - The more exercise your rabbit can get, the better. Mine are free range indoors, so they are all pretty active. The foraging food methods I use keeps mine active, healthy and most importantly not bored. If you keep him in a pen and/or cage, try giving him more floor time to burn some more energy. Make feeding an exercise for them and its a win/win.
Everything I've listed is a work in progress. I'm always looking for new ideas or way to help improve my buns' lives. Not everything I do, will work for your bun and/or your situation, but I hope this helps.
