This might be more of a Dine n' Dish request. But to answer and to bring it around to cookbooks, how about tofu scramble? There are tons of possibilities there, many found in Vegan Brunch by Isa Chandra Moskowitz. She also has vegan omlettes and other savory recipes.
Hm. Smoky Curls from Vegan Diner as a make ahead dish that you can reheat at breakfast? The dish itself doesn't take too long either. It requires soy curls but you can store those in the freezer until you need them.
Or maybe smoothies? Although I don't make vegetable smoothies I know some throw kale, etc in. That'd be fast.
Some people eat adzuki or other beans for breakfast.
Have you ever made a chickpea flour omelette with veggies? Technically this is not a grain as it is from chickpeas. If you google "chickpea flour omelette" there are a ton of different versions of it. I make this often for breakfast and it only takes minutes. If you want it totally from scratch you could grind your own chickpeas with a high speed blender, though I tried it and my tummy didn't like it for some reason.
This morning I had kidney beans and chard sauteed together and a little salsa on top. I eat a lot of beans for breakfast, sometimes as spreads and sometimes whole with veggies or on toast. I'm not sure why you are avoiding grains but there are so many healthy high nutrient dense ones to choose from, like millet, wild rice, buckwheat groats. I like to take raw buckwheat groats and add almonds and blueberries to it and just a tiny bit of water to soften it just a little but still retain a nice crunch. If you wanted it more savory you could eliminate the blueberries and add grated zuchini or carrot and savory spices, or other seeds and nuts and so on.
You could blow the whole idea of "breakfast" dishes out of the water and have something like bean and vegetable soup or just vegetable soups for breakfast, or a big garden salad, or a handful of nuts and a cooked or raw vegetable, the possibilities are endless. I make a sweet potato and black bean dish with savory spices sometimes (garlic, cumin etc), and I could see having this for breakfast too. You could make a big batch the night before and then have it for several mornings. A little goes a long way and is very filling.