as the driver performing all the services for the S-corp, I would think that from an IRS standpoint you would have to take a substantial salary leaving little remaining profits. even those profits are subject to income taxes but you do avoid the social security and Medicare taxes.
some states impose an income tax at the S-Corp level. as an employee some states would require the corp to carry worker's compensation insurance. in one state the failure to carry workers’ compensation insurance is a criminal misdemeanor, punishable by a personal fine of up to $10,000 or one year in jail, or both. For second offenses it goes to $50,000.
the standard mileage rate includes an amount for depreciation. that's why it's actual expenses or standard mileage.
about the best IRS info on this is PUB 463 chapter 4
https://www.irs.gov/forms-pubs/about-publication-463
