(1) could be corn, sorghum or milo, it's hard to tell until it matures.

(2) sounds like clover to me-cowpeas have large leaves never seen flowers

(3) most likely, although they could be the cowpeas or lab-lab if that was in your mix

(4) I would try to add some kind of feed away from the plot, not too far so they will still be close to your plot. sounds like your plot is just for harvest not for feeding so, as long as it's growing when you get ready to hunt it thats all you want? maybe pour some corn about 50 yards away from your plot.