Of the four, Table Rock would win hands down. The availability of lodging goes from family owned "fish camp" style resorts all they way up to major condo complexes and resorts like Big Cedar. Hotels in Branson can be downright cheap if you get them before Memorial Day. Outlet malls, shows, etc for the wives who don't want to fish. None of the boat ramps (even the private ones) can charge a lauch fee per Corp of Engineers rules. There's Silver Dollar City, water parks, putt-putt golf, and go-kart tracks for the kids. And TR has a good variety of fish (a guy like me can even duck down to Taneycomo to fish for trophy trout) or you can head to Bull Shoals, too.
It's a half-hour from I-44 at Springfield, divided four lanes on US 65 all the way to Branson now.
LOZ can be good for fishing if you stick to areas like the Niangua Branch (too shallow for most of those big yachts). Lodging for large groups is more difficult, but most family owned places have their own ramps and you can park your boat overnight in a slip with electrical hookups. Most places will have a beach or a pool, cable TV, etc. There is at least one big outlet mall, and Jefferson City is thirty minutes away.
I haven't fished Truman, Stockton or Pomme De Terre, so I've got NO information to share on those. And I'm still not against Mark Twain. Looking at the web sites, it WOULD be a good Rally location.
And my vote for time of the year no matter where would be May or October. Much more comfortable temps and humidity, and the fishing really picks up in these months.