Your coop/brooder/pen/yard set up sounds nice! What a project moving all of it tho!
IMO, the only thing you'll really have to put much time and energy into is the transitional brain reprogramming time (aka coop lockdown period) that they'll need in the big coop that they will be sharing with the chickens. You want to make sure the keets' little pea brains know THAT coop is home, or they may keep returning to the brooder coop, or choose to roost on top of it or in the trees instead.
So here's my suggestion:
You may want to section off an area in the big coop just for the keets to stay in after they are about 4wks old (instead of the usual 6wk age that's recommended by many), and then keep them in their new section of the big coop for about 6 more wks (so they can get a little more close contact with the chickens, see them come and go all day, but are separated by wire still), and then after the coop lockdown period start letting them out into the coop and the chicken yard with some of your gentler chickens, but be sure to herd them in every evening around the same time to establish a routine (if they don't willingly follow all the chickens in on their own). Hopefully you can establish the routine of going in before they figure out they can fly out of the chicken yard! You might not have any issues at all getting them to "coop up" if they can learn the routine from the chickens. Routine is key with Guineas, so the more diligent you are from the get-go the more it will pay off in the long run for you. Hopefully they will integrate just fine with all your chickens and just blend in and go with the flow. Raising them with a few chicks that are close in age may help too.
Now, having said all that... please (if you haven't already) read all the previous threads about aggression issues some poultry owners have with co-mingled flocks. Hopefully you don't have any of those issues since you have a spacious coop and yard, and you let everyone free range, but it never hurts to be prepared just in case you do have any problems, especially during breeding/laying season.
As far as brooder temps go... IMO, you may want to just provide a low watt bulb (40-60watt) in a brooder lamp hood for the keets just at night for a little while, maybe up until they are 3-4 weeks of age at most. They definitely don't need the heat during the day, so no need to waste the electricity!
Good luck, hope all goes well/smoothly for you. Post some pics if you can!
