The tours are backstage glimpses of the Disney magic. I would highly recommend the Keys to the Kingdom tour. We went on this during our last trip and absolutely loved it!

You get to go into cast member areas, through back entrances to certain attractions, and learn a lot of WDW history along the way.
We have never used the reserved fireworks seating, to be honest. But, we have seen the areas and think they are good locations for viewing.
The meals are the best part of the plan, IMHO. You get unlimited meals anywhere you want except Victoria & Albert's. Unlike the regular dining plan that has the hassle of counting CS and TS, you do not have to count a thing with this plan. You get three meals a day, anywhere for the length of your stay. You can eat all TS if you want or mix it up with CS. For each meal, you get a drink, appetizer, entree, and dessert; that's for each person on the plan as well.
I would recommend taking in one of the dinner shows, trying Keys to the Kingdom, and seeing La Nouba. Try at least a TS each night too. We usually do two TS's a day, a tour, a dinner show, La Nouba, etc.