Answers to 2 questions from wbbnospam:
Re: Using your imagination to make a 'Verse costume
One reason I love Browncoats and the 'Verse is that there's a lot of room for creativity. I love looking at the costumes in the background of the scenes; the complexity of the 'Verse is visible in the variety of what is worn. Shawna Trpcic did a wonderful job with what was probably a limited budget. Even at the Shindig, she used backlot clothes for most of the extras, but combined them in unique ways. European-style ballgowns look exotic when combined with Asian shawls and Elizabethan headpieces.
So I can't see that anyone would be critical of your creative efforts. (On the other hand, if someone showed up dressed as a character from a non-Firefly/Serenity universe, I'd have to wonder why they were there. It would really break the mood.)
Re: Charlotte weather
Given that our weather this year has been exceptionally warm, and still is, it might be a bit hard to predict. But here's the 'normal' in late October:
Highs in the uppers 60's/lower 70's; lows at night in the high 40's.
October days tend to be sunny, with little rain.
Because Charlotte is in the Piedmont, the cold air from the mountains can make the nights chilly. It depends on the winds.
For a forecast, try: http://www.charlotteobserver.com/weather/
See you soon!