I have lots of Mourning Doves too. They are getting quite assertive. While they do still putz around on the ground picking up what the other birds drop, there are 2 or 3 of them that challenge the Cardinals, Titmice and others for the open feeder and they will perch in position on a nearby tree branch seeking opportunity right along with the others. I guess they've decided to go straight to the source, rather than waiting for leftovers.
Do you have any Blue Jays ? They can teach those Mourning Doves a thing or two about assertiveness. LOL One of my BILs mother lives in Arkansas and she, too, has a yard full of birds. She has lots of bird houses and feeders but in the winter she also makes a few feeding stations that hang from tree branches or on plant hangers outside her kitchen windows. She winds a length of fine wire around the top of a pinecone then coats the pinecone with peanut butter and then packs birdseed all around the cone. She says they love it.