I'm over in Chisago county. My aunt lived in Elk River years ago. I had a friend break me into chickens several years ago, at my request. Now she's my sheep enabler, too. My first flock was a mixed heavy breed special from Sand Hill Preservation. I got 50 little chicks and a checklist that said how many I had of each, but the chicks themselves were not marked. The kids and I had a lot of fun figuring out what we had. There were blue jersey giants, iowa blues, speckled sussex, orloffs, gold and silver laced wyandottes (not all on one chicken!), rhode island whites and reds, orpington, cochin, mottled java, and I can't even remember what else now. My prize Rhode Island Red rooster from that batch died earlier this winter. He was so sweet we could just pick him up and walk around with him. I think you'll like the breeds you have. I imagine you've done your research on temperament if you chose those for your first flock. I haven't ever had Ameraucanas, just the easter eggers which are usually either off-type/sport Ameraucanas or mutts. I have layers and also raise meat birds for myself and others.
I usually brood in the spring, because I do not have an indoor brooding area. I have a night box with a run - the heating plate or (in the past) heat lamp for chicks was in one corner of the box, and I put food and water out in the grassy run. The chicks would go in and out and self regulate themselves. I think they feather out quicker that way. This is totally outside, though, and typically not until last week of april/first week of may.
You may enjoy this thread. http://www.backyardchickens.com/t/956958/mama-heating-pad-in-the-brooder-picture-heavy-update Any way that you can let them come and go from the heat will be better for them. I was considering the ceramic bulb - a reptile bulb, right? - that you're talking about when I switched away from heat lamps. I think you could definitely set something up for them with that, using the cave idea in that thread.
Here's another idea you might like: http://www.plamondon.com/pasture_hover.html
Don't be shy about pictures!!
I am not sure if my reply attached to this specific comment so see my reply below..lol i am pretty techy but i don't spend a lot of time on bulletin boards anymore.