Line a large baking tray with baking paper. Place pumpkin, onion and whole, unpeeled garlic cloves on prepared tray. Sprinkle with spices and drizzle over 2 teaspoons of the oil. Toss well and spread over tray. Bake in preheated 180C oven (fan-forced) for 30 minutes or until pumpkin is tender. Cool on tray.
Transfer pumpkin mixture to a food processor with chickpeas. Season with pepper and process to form a thick paste. Transfer to a large bowl. Stir in flour and coriander. Shape heaped tablespoons of mixture into balls and flatten slightly. Place in a single layer on a baking paper-lined tray. Refrigerate for 30 minutes.
Heat half the remaining oil in a large, non-stick frying pan over a medium-high heat. Cook half the falafel for 3-4 minutes on each side until golden. Transfer to a tray. Repeat with remaining oil and falafel.
To serve, spread wraps with beetroot dip. Top with lettuce, cucumber and falafel. Thin yoghurt with a little cold water and drizzle over filling. Wrap up to serve.