I don't have much experience holding brisket, but a couple of restaurants around here that serve it, wrap it with plastic and hold in their proofing oven/heated cabinet with varying degrees of success. It seems to hold up well the day of the cook, but I haven't had it on the second day where I felt it was suitable to serve. I would suggest this be one item you're willing to 86 as the day progresses unless you can stagger cook times.
Ribs can be handled much the same way as brisket, but I'm not sure I don't prefer to wrap them in slabs after smoking and refrigerate them before serving. Then reheat on the grill and sauce to order. This is how most chain stores handle ribs and it either works, or the public doesn't know the difference, you pick.
I would do chicken, turkey, and sausage the same way if I couldn't time my cooking to result in a boost of supply at high demand times. Chic and sausage both heat up well on the grill, and chicken can also be kept in the sauce for several hours if you choose to do a saucy BBQ chicken.
Pork loin I would only do if I could serve fresh from the smoker unless I planned to serve with some type of sauce.
Pork butts and shoulders can be held for several hours before pulling if needed. One restaurant I've worked with around here pulls all of their pork in the AM, sauces it, and stores it in the fridge in deep hotel pans(wrapped). They then use their steamer to reheat the still wrapped pan. This works well. Then any remainder is mixed 50/50 with fresh the next day for serving unless it can be used for brunswick stew or beans.
Brunswick stew is a great way to stretch the usefulness of a product since it can contain chicken, pulled pork or pork loin, and maybe even sausage in varying amounts so it can collect a lot of things that might otherwise go to waste. Even if you sell it at half price, it still makes a little money from what might have been lost food cost.