Place pears, cut side up, on a small baking sheet and drizzle with 2 tsp olive oil. Roast on upper rack of oven until soft, 20-30 minutes. The riper the pear, the less time it will need. Let cool slightly.
While pears are roasting, toss almonds, pumpkin seeds, brown sugar, oats, salt, and remaining 1 Tbsp oil on a small baking sheet. Toast on lower rack of oven, stirring occasionally, until golden, 10-12 minutes. Remove from oven and let cool.
Whisk greek yogurt and honey together in a small bowl. Spoon yogurt mixture onto plates and top with pears and nut-oat crumble.