Looks good! That's the size EcoTerra I have; I got 1.2 brevs (about the same size as spectrals?), and could have easily accommodated 1.3. The ferns may or may not work out in the long run; none of my ferns made it (I think the light was too intense for them; maybe I could have provided more shade). Orchids have done wonderfully; every one (five total) I put in in January is still going strong, and they've grown.
You'll ultimately have to suit your misting to what your eyes and humidity gauge are telling you; one moderately heavy misting in the morning was fine for me during the spring and summer, but now that the furnace has kicked on, I need to do the heavy in the morning, lighter after work routine (like adamkwas said, an hour or so before lights out, so things can dry down a bit before bedtime).
I'd love to see pix of your pygmies once you get them!