Have you ever worked in a restaurant? What you're describing would be a massive undertaking to manage with just a single corporate partner, much less with a collection of independent and small chain restaurants.
If you force restaurants to optimize everything for timing, you'll end up delivering food on par with McDonalds.
And if it turns out customers are willing to pay restaurant prices for McDonalds quality delivery, then McDonalds themselves will start a delivery service to compete with you.
