Few butt questions for party???

So next w/e we are having about a dozen people over for my first little egg party and was going to cook two 7.5 lb pork butts,4 racks pork spare ribs and two spatchcock chickens.So my plan is to cook the butts overnight friday indirect at 250 then the ribs sat afternoon at 250 when butts come off  as egg will already at the correct temp.I'll cook the two chickens at 400 raised direct at the end for an hour.

About how long per pound for pork butt at 250-270 indirect?
About how much lump for overnight cook,is the top of fire ring enough?
Is the oval stone required cause if not id have room for butts and ribs at same time? (I have adj rig with R&b oval combo).I also have spider and smaller 13" stone and could cook  ribs and butt together but figure the spider would take up some space down low and limit my lump space and that the smaller stone on the spider could burn the rib ends???

Finally I ashamed to say i've never had pork butt before so what kinda sauce (if any) goes good on pulled pork sandwiches?

thanks.