I live in NC bbq country...which we have a mix of sweet and vinegar-based bbq sauces. You can sauce it how you want. We have both pulled pork, but a world famous bbq place nearby sells sliced pork. They cook their roasts and then thin slice it... If you place an order for a sammich, they take the precooked, room temp or chilled pork and put it on a griddle to heat up under a lid (to keep steam/juices in). Sliced pork in a sandwich can have a little more bite to it.
Boston Butt(shoulder) is typically what you want to smoke for BBQ, but picnic roasts are sometimes cheaper or more readily available. My wife's uncle does a lot more half-loin roasts...leaner white meat and less fat. He'll sometimes mix that in with a boston butt. This is the kind of guy that owns a $3-5k bbq trailer he bought years ago. He catered all his daughters' weddings and numerous family parties...is active in his church doing bbq, but it's not a business to him.
For Boston Butts, they're really hard to mess up if you get a meat thermometer and take them out when they're the right internal temp. (180-190 degrees depending on fat) Once the fat inside melts and breaks down, you're good. Best results for a bbq party come when you cook the roasts to completion an hour or two before the event....then wrap in foil and store in the bottom of a cooler with towels on top to contain the heat and take up air space. That keeps the pork hot/warm and letting the meat rest that long, before pulling, allows juices to do their thing. It CAN result in top notch bbq. I think we did a party 5-6 years ago where my dad was supposed to be following my instructions on cooking...he got the fire going about 5 times too hot. The roasts were done 4 hours earlier than I thought possible by internal temp. I had him store them and they turned out fine.
I like pork ribs. You can get those and cook them on a gas grill for 3 hours. Sauce them every 30 minutes to keep them wet...or do a dry rub. Get some match light charcoal and make a foil cup to hold the charcoal.....and let that smoke permiate the ribs as they cook in the beginning. You'll end up with charcoal flavor, but the slow-cooked ribs without the effort of maintaining the fire. Pork fat is best when slow-cooked and melted away. If you cook it too fast or under direct heat, you can end up with a fire burning off the fat or burn the outer layers and undercooking the inside.