I don't mean to come off the wrong way, but from the sound of your post, you are not prepared to cook and coordinate a meal for 200 people.
Here's my other thoughts:
1. I'm glad I'm not paying you for this nor eating it. Sorry, but I do not condone pre-cooking, bagging and re-heating pulled pork...just because you don't think you have time to do it on serving day. Tough squat. Man up and do it right.
2. That's way too much baked beans. "Doctoring them up" is a wise suggestion. I do that and receive the "these are the best baked beans I've ever had" compliments. For 200 people, I would prepare 7, maybe 8 half-size pans. You really need to analyze the ages of the attendees and go from there. More kids (3-9) and older folks (55+), I might even consider 6 pans.
3. 125 lbs of raw butts is going to be about right for the amount of finished pork. That should be about 12 whole butts. I would certainly allow for ample cooking time and hold them in coolers/cambro. I pick most, if not all, of the fat out of one when I make pulled pork. This takes about 10 minutes per butt. Yes, that is roughly 2 man-hours for this project. Get some help. You better have help anyway for 200 people. Pull the pork, put it in 1/2 size pans, squirt some 50/50 apple juice and cider vinegar on it, cover with HD foil and either put back in the cambro or 200F oven to keep hot.
4. I would have the equivalent of 6 half-pans of potato salad. Probably 2-3 pans of cole slaw. I don't know, I don't prepare or serve or eat it, so I don't care. I've NEVER had anyone demand it (client) or ask for it (guest).
5. As far as cooking the beans, heat them in a 250F oven for 2+ hours.
6. I would buy about 160 buns (4") and only put out 30-40 initially and just put out a dozen at a time.
I hope you have chaffing dish racks...it sounds like you don't. I would get some, along with full size pans and sterno. Put the sterno under them, put 1" of water in the full size pans and put your beans and pork over the water.
I also set up my serving tables so that a line can go down each side of the table. I will usually have 2 complete tables set up, serving 4 lines at one time. I can get 175 people to fix their plate in less than 20 minutes. It is intense, but you need at least 2 people watching the lines at all times, getting refills ready. Sauce needs to be in bottles at the end, along with knives, forks, spoons and napkins. Don't make people pick all that crap up in the beginning and hang on to it. Have only plates and buns at the start.
Drinks are either at the end or on a separate table.
Me and my wife recently did a wedding like this for 175 people. We had pulled pork, ribs, beans, potato salad, broccoli slaw, some asian pasta salad she made, buns, a few burgers, and some grilled chicken for a few special diets. We worked 2 14-hour days to pull this off. Just me and her. We made every single thing we served from scratch (well I did dump beans out of a can.) Other than that, it was peeling 70# of taters, boiling 3 dozen eggs, etc. Trim, inject and rub 8 butts, 6 racks of ribs, patty burgers, trim chicken, etc. Mix sauce, bottle it, etc.
Lot of hard work, little sleep but to have nearly 150 people come up to you after it was over and say that it was the best food they've ever had was worth it.
Good luck.