I think I read maples were the best trees or maybe certain hardwoods vs. pines.

I believe I read 2-3ft above the ground and trees diameter 3-5" ideal.

Personally I'd hing them in the spring, not now...

definitely can help add cover.

also if you're clearing trees, rather than cutting them completely down, why not hinge cut them?

one patch of woods we use to hunt naturally had a big oak fall every year or 2 and that alone created cover and did notice deer seem to like that area.