rates questions

Depends on what the commodity is.
In my opinion: Owner-operators minimum: 2.50 per mile power only, 3.00 per mile with trailer.

Owner-operators have many fixed and variable costs: payments, maintenance, repairs, taxes, amortization, depreciation, fuel, plating, licensing, insurance, permits, fluids, tires, windsheilds, washes, food, showers, lodgings, stationery, sundry, parking, specialty equipment, tolls, health insurance and their own wages, with income tax, to come out of this money.

Company drivers with good experience: priceless.
Good ones worth minimum $25/hour plus benefits.

There are costs related to being away from home (food and showers, mainly) and it needs to be worth missing your family or being lonely.

In the USA its an 11hour per day driving window with 3 hours of work or waiting time. 70 hours per week total.
In Canada it's 13 hours a day driving and 1 hour work or waiting time. 70 hours per week total.
North of the 60th parallel it's 15 hours a day driving with 1 hour work or waiting time. 80 hours per week total.

If this is a question on how to keep a happy workforce running trucks for you, pay them right (no mistakes and on-time), treat them with respect, listen to any operational issues and make somebody available to fix any problems beyond the operator's control 24/7.

You can also figure this out by pricing out everything yourself on the internet.