Hello
I'm from the group bangbangneko (one of the girls) any ways if your looking on doing a skit that's great. Here some things that we've learned from doing a skit.
1) recorded CD vs. mircophones: recorded CD is the best because from what I've seen and heard you can't have a mircophone. You've gotta use your loud voice, which if it's your first time will be very scary and hard. So go with cd it's easy and I'll you have more time to focus on getting the lib sync right and acting right.
2) coming up with skits is really hard, we have to go through many many ideas till almost time for the con when we finally have one that works. So what I would do is just look into what kind of skit is it going to be, a big crowd pleaser are usually funny ones. Like making fun of yaoi (which we did with the ymca song)or some kind of twist that gets the crowd going. Also maybe look into what other skits have done to get ideas (youtube is a good source) but if your doing one that is serious make sure you present it well or you'll lose the crowd.
3) Make sure that you have the time to practice because the crowd doesn't like to sit for minutes and watch a skit that has good audio but have bad acting. Also make sure you have a group that is willing to make time for the cosplay, since your going to have to go into meetings during the con. So that the staff can make sure everything is ready so that there will be less stress for them.
4) If your looking for people to do a skit look for a anime that you can make skit for then either post around the forums or ask your friends, maybe you'll find someone if not maybe look into doing a skit by yourself like the "vash skit" where he went up and did a monologue.
Well I hope this helps, and I hope I didn't scare you cosplay is allot of work but long as your having fun that's all that counts.