Je propose Bevagna and Trevi, with the latter also including the waters @Clitunno di Trevi. October in Bevagna would include their excellent Labor Day long weekend, an appealing fest separate from its earlier summer medieval tourist event. International food booths, the annual Communion for tweeners and sometimes a special play in the town's tiny, perfect and authentic historical theatre, comprise that long weekend.
Montefalco on a Saturday would give you a two-fer: brunch say outdoors at Alchemista, with the weekly Flower Market spread across the square directly in front. Castelluccio is an absolute must, maybe consider trying for the sunrise there coz you might just get lucky and witness one of the village's awesome thermal 'inversions', one of travel's great moments. The *entire Piano valley fills with a milky fog.
Spello has the wonderful Cafe Propenzio. After I gave it a shout-out over on Thorn Tree, some snarky Brit snobs put it down as 'pandering to Americans'. Damn the torpedoes, those smug critics are wrong. The wine there is world-class.
Spoleto is also not to be missed.
Bonus: one of the area's best-kept secrets is The Abbazia San Pietro in Valle. The abbey-church itself is open to visitors, with its ancient paintings, but the whole property is a family-run wonder, with incredible views. The lodgings are a splurge but not too expensive. Breakfasts are worth waking early for, in a courtyard with plenty of authentic historic charm. We met a Colorado couple there who'd come for their 7th straight October stay in order yet again, to hike the trails.
Norcia was wrecked in the quakes too---is it back on its feet for visitors and locals yet?
I am done. the end.