For a safer firmware build, try modifying the PWM table for the DD FET. Like, cut all the values in half. Then turbo would be limited to only 50% power. Or whatever other divider you prefer.
Calculating a whole new ramp is an option too, but it’s more difficult. I had to manually tune the TS10 ramp quite a bit to make the low modes smooth.
Or, of course, just setting a lower ceiling level and setting the turbo style to none. That covers most needs. However, strobe modes would still reach full power. The ramp table method is a more complete solution.