I don't think I would use Mooney and soft field in the same sentence. That is really not a good place to be... Even with our older mooneys, the nose is just too heavy, and gear as sturdy as it may be, a little too fragile to risk on a truely soft field. Combine that with the prop clearance, it is a high risk operation in my book.
I don't have a problem with grass, but if it is rough or soft, I would be pretty hessitant.
With that disclamer out, If the indigenous folks were after me with their spears,,, I would focus on keeping the speed as fast as reasonably possible and try to balance bringing up the nose wheel. Don't just lift off the wheel like a cessna, try to ease if up into the air. It takes a little practice, it seems to me if you try to pull the nose up too strongly, the plane does not accellerate or fly near as effectively.
Personally, I would wait for the field to dry..
craig