I'm not sure I could fit in much more veg without starting to remove other food groups from my diet.
I'm not sure what you mean by this.
You shouldn't need to take out the foods that don't affect you if you add others.
Fodmap is about triggering foods, (high in not the actual number of foods.
It's also supposed to be done for around 8-12 weeks, then trialling new foods gradually, under medical supervision, to see how you respond.
This is just one list I grabbed online and there are quite a lot of things that can be eaten.
-Proteins: beef, chicken, eggs, fish, lamb, pork, prawns, tempeh, and tofu
Whole grains and starches: white and brown rice, lentils, corn, oats, quinoa, cassava, and potatoes
-Fruit: blueberries, raspberries, pineapple, honeydew melon, cantaloupe, kiwi, limes, guava, starfruit, grapes, and strawberries
-Vegetables: bean sprouts, bell peppers, radishes, bok choy, carrots, celery, eggplant, kale, tomatoes, spinach, cucumber, pumpkin, and zucchini
-Nuts: almonds (no more than 10 per sitting), macadamia nuts, peanuts, pecans, pine nuts, and walnuts
Seeds: pumpkin, sesame, and sunflower seeds, as well as linseeds
Dairy: lactose-free milk, Greek yogurt, and Parmesan, Colby, cheddar, and mozzarella cheeses
Oils: coconut and olive oils
Beverages: peppermint tea and water
Condiments: cumin, saffron, cinnamon, paprika, coriander, cardamom, soy sauce, fish sauce, some chile-based products, ginger, mustard, pepper, salt, white rice vinegar, and wasabi powder