I'm not stopping you from putting together or training your own team when you're on duty.
I mean for any time when you know you need time off. Dr. Helen Cho is friend, and a geneticist and physician. She's worked with us when an Avenger was wounded on a mission in Sokovia, and she's a specialist in tissue regeneration. She's still on the payroll as a medical researcher at the Avenger's HQ. There's no reason why she can't be on call when or if you really need her. At least until we have a qualified alternate doc.