The OG team of Shaun Prentice and Jill Benson of Australian doctor burnout work have added a third author Margaret Kay and devised a model of sustainable GP work.

They see GP work as a series of tasks. They reflect from earlier and other studies (Shanafelt, Ko) that the more rewarding tasks we are engaged with or that align with our values(Prentice & Benson), the more satisfaction we feel and the more protected we are from burnout.
In the fulfilment of each task, there can be psychosocial factors (referring to the GP here, not the patient) and Enablers (administrative, tech or workflow elements that smooth the way) that weigh on the demands

It is easy to relate how niche work then looks there – the tasks making up your desired work likely have psychosocial enablers (it is tasks pt ask for, not what they are told to do), pricing and expectations can be clearer, and the GP may be working with the pt cohort that suits their personality. Enablers in niche work are stable workflows, ability to create focused resources and delegation. The task will likely be meaningful to the GP – that is why they choose that niche! So although there may be complex tasks and demands, the meaningfulness, enablers and psychosocial milieu add up to a balanced see-saw.