I voted Friday before I read the particulars.
Sounds like an interesting scenario. Trust Bob's comments, and do the due diligence. I considered moving a slam to a bar, but Richmond is a tobacco state, and Salem and other cigarette companies partner with bars to push sales. Not all poets smoke, and it's hard ot build audiences in a venue that sends your folks home stinking.
I second that you must ensure the venue owner/manager has laid out all their cards. Our first venue was a little sensitive to the language and subject matter. Some want a piece of the door or a minimum in food/drink sales, which can hurt coffers.
If this venue doesn't work, a good place to try is an ART GALLERY. They control their own hours and can, with a small fee, obtain a one-night liquor license. So long as they have chairs and someone has a mic, etc., it's a lot better than worrying about an entity that is concerned about its bottom line and might pull the plug on you one week before the Grand Slam.
As for nights, I've learned that Mondays are tough to market due to their location behind the weekend, Thursdays are popular in our college (down)town (Richmond, VA) and there are a lot of events going on, but Tuesdays are good. Saturdays work if you have a parade of good features.
Sorry so random. In general, I'm skeptical of bars and can't stand being drowned out by an espresso machine or blender at a coffee shop.
But hey, if it means a new (or continuing) poetry slam, <picard> Make it so! </picard>