I might opt for grey [doesn't show dust and dirt] but a soft flannel pant, roomy sweater and sneakers will suit any age, any shape, almost any casual place.
Cute Fall Outfits: How to Dress Well, Feel Great And Look Even Better - Cute Fall Outfit Ideas
We are loving this sleek and slouchy look by Figtny. Try and recreate your own version by pairing comfy joggers with a leather jacket and some fresh sneakers. Trousers/Sweater/Bag: Aritzia, Jacket: Mackage, Sneakers: Adidas.