I have setup a mechanically mixed bird before .. its was the Kinetic 50 I used to have. Your throttle curves will be different only if you dont use governer.. Regarldess of what.. your throttle curves are different than your normal electric heli.. mccpm or not. I can give you those if you need them..
Pitch curves are about the same.
If you donot have someone flying with you, or a companion who can tach your head speed when hovering, you definitely need a good governor.. and by that I donot mean align or gaui or all.. cause you still gotta tach your head on those.. You need something like Mulitgov pro where you can just defin your desired head speed and gear ratio and governor tachs everything itself..
IF you dont have a governor or a tachoometer, you will need to almost never run 100 percent throttle on your engine, esp being a plastic head, you will blow it in peices..
Are you ready to do full setup of your heli? tell me when you need that.. I can help you set it up in detail with whats and why and hows.