I think stairs are the way to go if you have the time and motivation to build them. It’s a lot of effort up front but once you make the steps you shouldn’t have to touch them for many years.
Switchbacks can have erosion and drainage issues if you don’t put significant effort into their design, and maintain them over time. A straight scramble up the hill is going to get annoying really fast, and also have erosion issues.
Edit: There are some great trail building guides online if you hunt for them. Though they usually focus on trails open to the public that will get substantial use. If this is your private path then they are probably overkill for your needs.
https://www.americantrails.org/resources/basic-elements-of-trail-design-and-trail-layout

































Nice!
All that bare ground makes me so sad, though. My local hill has better coverage than that, but not for long. I’m worried they will have to shut down next week due to all the warm days in the forecast.