Lightly blanched or steamed English peas with butter and tarragon. Because peas just seem to go well with risotto.

Ooh yum. I would recommend a tart green salad. Think arugula, pomegranate seeds, green peppers and your favorite punchy vinaigrette with lots of citrus. I would also consider additionally serving a light soup - like a spinach soup. You take fresh spinach, stock (chicken or veg), melted butter, salt, pepper and milk/cream and blend into a soup - and then use fresh salted popcorn as the garnish.

You need meat. Like roast chicken. Or veal saltimbocca. Or like pierino said, osso bucco.

But if you are vegetarian, then definitely do the greens, and some big, meaty portobello mushrooms.

Dark greens sound good like Mr_Vittles suggested--how about sauteed swiss chard and shallots with some brown butter bread crumbs and lemon zest on top?

Myself, I would do it the other way around and serve the risotto as a first course to something like veal shank---unless you are trying to go all vegetarian, like.

Sauteed kale or broccoli rabe? Saute with olive oil, garlic, and lardons of bacon. Finish with a squirt of fresh lemon juice.