the caramelized onion butternut roast with chestnuts in the Veganomicon was what I did in a similar situation, it is traditionally and fantastic. You might want to double anything you do so you have enough to eat and share.
That sounds perfect! Lots of harvest/holiday ingredients, adventurous but not weird. Although I would totally love stuffed mushrooms or a leek cassoulet. Yum, yum, yum.