Fragrance free baby wipes and or vinyl cleaner will work on the canvas but very carefully test on a small spot first at the bottom of the bag. Don't use magic eraser on the canvas. as for the Vachetta handles Lovin my Bags is recommended for the Louis Vuitton Vachetta leather but other high quality leather cleaner / conditioners might be appropriate but you will need to be careful with that.
Also Regarding the canvas, it could just be the lighting. I purchased a pre-loved Damier Azur Speedy off Ebay and it would look dingy in certain light and then bright and pretty in other lighting. once you know you've removed all the surface dirt that may be there and you know that it's clean, decorate it with a cute purse charm and carry your bag with your head held high! : )
You can use wipes on the leather but they might dry them out since they remove the top surface of the leather along with the dirt. You should condition the handles right afterwards. I used a magic eraser on my Delightful's handles and then used a leather conditioner. Wilson's and Apple are pretty good products. For the canvas I use alcohol free baby wipes and if it's really grimy I use some dish liquid on a wet washcloth. I wouldn't use the magic eraser on the canvas though!