“employers will respond by paying lower salaries BUT with lots of non-pecuniary benefits (trips, cars, fine dining, etc.).”
No, those things are already taxed. How about shorter work weeks?
Welcome to France. I can just see myself sitting half the day sipping coffee in a cafe sneering at tourists, and wiling the nights away burning cars.
Maintain the same hourly compensation, but cut your work schedule to every other week or 4 hours work/4 hours unpaid time off each day. The 4 hour schedule would likely service your good customers while cutting the costs at a time when there is little business on the table. It solves the too much income, too much tax and cuts your work load at the same time.
The 4 Day Tire people used a model that opened for business on the 4 best business days. That's a possibility as well.