Make sure you're giving the darkest green greens you can. Kale is good, but the romaine and leaf lettuces aren't really that nutritious. Try Mustard and Collard and Dandelion (as dillan2020 noted) if you can get it. Always give more veggie than fruit as they have a sweet 'tooth' and will eventually ignore the veggies entirely.

The best lists to check out aren't the 'good and bad' lists, but the ones that show the ratio of Phos. to Calcium. Iggies need a good balance of calcium in their veggies, but not too much. My girl, a rescue, had been given nothing but fresh spinach by her first owner who thought it was perfect because of all the calcium in it. Well, too much calcium led to MBD and she ended up with a 90 degree kink at the base of her spine that stunted her growth and made moving around tough. Not to mention it took forever to get her to eat a balanced diet after that.

I used to have a link to a great list of Iggy foods in order of ratio...but I lost it. If I can find it again I'll post it here for you.