What would you serve with this? Since the "side" dish is almost taken care of with the vegetables I'm not sure what to add to it! Is there a gr...

I could see serving this with a puree--celery root might be nice. Or even some long grain white rice, which might be slighlty lighter than potatoes. As for starters, what about a chilled soup like this one: http://www.marthastewart.com/332827/chilled-fresh-pea-and-buttermilk-soup
There are a number of great soup recipes on this website, but I was thinking chilled might be good given the time of year.

Sauteed or fried mushrooms might work; thyme is a good mushroom herb. But hopefully Tom will answer your query himself.

maybe some crusty brushetta?

I'm always a fan of a green salad with dinner. You could also start with a soup like curried butternut squah.