Avalon, if you are literal with early Fall (after Sept. 21), you may find this a hard to fill list. 1000' makes the list pretty short too, as this knocks out Eldo, most of the S. Platte, and Lumpy. You get left mostly Black Canyon (few longer 5.8s or lower), Flatirons (low angle), or a lucky Sept. or Oct. day in RMNP. Also, the north-ish aspect climbs higher get cold by late Sept. for most. Consider linking two shorter (500') climbs to broaden your options or coming earlier than Fall. If you're willing to do crampons and tools, your options broaden somewhat, too...but you only listed a rock grade.
Leo Paik From Westminster, Colorado Joined Jan 1, 2001 22,015 points