[lschwart]

I agree with the consensus here:

Use the L1 on the floor.

Set up the Sennheiser for vocals and have the Beta57 available on another boom stand for guitars that have no pickups.

A stool is a good idea for the folks who want to play while sitting.

No pedals.

But I will add that you should get a simple DI box to make it easy to have all the pickup signals go to one mic channel on your little mixer. This will also let you put the mixer where you want without having to worry about the length of the performer's cable. All you'll need to do for each performer is to quickly set the gain on the channel and maybe do a little EQ adjusting, along with balancing the guitar and the vocal--although no one will be performing all that long, so you won't have time for any ideal dialing-in. Get two DIs if you think you may be getting some duos, etc.

Bring a few instrument and a few mic cables. They fail, and people don't always bring their own. Keep the instrument cables fairly short. 10-12 feet, just long enough for the performer to plug into the DI box at his or her feet. The mic cable can be as long as you need it to be to reach the mixer.

Pay attention to where you put the L1 with an ear to possible feedback problems (especially for the people who need to use the mic for their guitars). It may take a little experimentation before you find a compromise position that works for most performers. You won't need a lot of volume, so it shouldn't be that tricky.

Louis