That many coops really helps. And as (I think) they all have separate runs, that will really help. Because this allows you to separate birds that do not get along.
So, I think I would pull the Keets to one coop, ASAP. That will solve your feed issue. They are more than old enough to be without mama.
I would wait till the Mama forgets her chicks, and then put the single chick with another single chick in one house, and keep them together until they agree to get along, then add another pair, wait again, then put all the chicks together. When you add a lot, it reduces the concentration of picking on a single bird. If you just add your single chick, EVERYONE will know that chick does not belong and try and get their digs in.
After the whole flock of chicks is getting along - I would add the hen to that group. She will probably peck them, but it will be hard to chase them all, and I think she will settle down fairly quickly, but still be queen bee. This will work for a while. But fairly quickly none of those coops will be big enough for 20 head. You can cheat when they are smaller, but eventually you are going to have to either cull some birds (just remove them from your flock, point of lay birds are easy to sell) or split the flock into two groups.
You should also add some clutter to the runs, tipped over boxes, mini walls - scrap pieces of plywood, some roosts, multiple feed stations in the run. Make is much safer and more entertaining for birds. Birds can get out of sight of other birds, important in chicken society.
My ultimate goal would be to have an empty coop, when you are done finagling. Because I think that you are trying to be proactive, but are inexperienced, and I am pretty sure in all those birds, you are going to eventually have some wrecks, and an empty coop, would be of great help.
I am not real sure, but I think keets are going to take a lot of space, and need to free range quite a bit. My grandfather had Guinness to keep the snakes down, and they roosted in the trees, but I have never had them.
Good luck,
Mrs K