I think it's a last resort kind of development. We have other ways to increase crop production and production area. From what I've heard/read some crops show a very good production with no till farming. A layer of cut grass/hay is placed over the field and protects the seeds. It limits exposer, erosion, and doesn't require the same quantity of pesticides/fertilizers. With some crops it increases production without all the side effects. It doesn't apply to all crops of course but some of the staple crops look promising. Hopefully we'll see a large scale implementation on it somewhere to see how it works.
There's also the buildings for crop growing that I think was mentioned in this thread once. It only makes sense. It can increase crop growing area indefinitely. The only limits are how high and wide you build it. I'm definitely in favor of that idea before we go modifying crops to allow people to cut down more forests.