I also finished the second pair of Halloween pants last night, but Thing 1 has not yet tried them on. These were cut from the KS 3042 (pajama) pattern. I want to see how the fit compares to the KS SFC ghost camo pants, and I'll probably post pictures. At any rate, I was glad to finish them in plenty of time for Halloween (though I'm sure Thing 1 will wear them after Halloween).
This time I cut and sewed the outer and lining pieces separately, then put them together to sew the leg hems and waist elastic. I'm pretty happy with how it turned out! I think I'll do this again! Not that every pair of pants I sew for Thing 1 needs to be flannel-lined, but he'll probably outgrow some of these so fast that it's not a bad idea. And then the only serging I do is the waist and hems, prior to turning down and sewing. The rest of it is lined, so it doesn't matter.
I still need to work on the new shoes for Thing 2, and I've got more pants on tap for both of them.