For each tool, the current settings can be set as the default for that tool.
After making changes, click the Defaults button at the bottom left of each Properties dialog, the Default Settings dialog box opens:
To save the current appearance of the tool as that tool's default, click the first option button and OK.
To restore the system's default settings, click the second option button and OK.
These default settings will only apply to the current tool.
This default setting will not "Lock Current Tool".