It's an interesting question.
It seems to me that there aren't any one-size-fits-all practices. I don't think it would be appropriate to mandate that all farmers must implement a particular practice, because each piece of land is a bit different and each farmer's needs and their market, and so on, are different as well. I suspect that in crafting policy it would be important to leave the flexibility for the farmer to play a key role in determining which practices are right for them and for their land. That's what I think.
Also, there might be a sort of ladder. You might begin with a practice like cover cropping and then step up to adding shelterbelts and continue adding additional practices over time. It would be useful to build in a mechanism that allows farmers to continue to ratchet up their climate impact in that fashion.