I have been at the Maldives about a dozen times (twice last year), including several live-aboards and been in about 10 atolls (only missing the very far north and the southern ones). However I have not been on the Stingray (but I've heard good things about it).
But I can add some things to it: the Maldives is mainly a European/Asian destination. You'd be very lucky if you see another American - the Stingray is offered e.g. by German travel agents and you can end up with a boat full of Germans and then language can be a problem. Diving is usually European style: up to 3 dives a day (usually two before lunch, one in the afternoon). Most dives in the Maldives are drift dives and/or because of the the coral bleaching 12 years ago the best corals in the northern atolls are deeper (60-100ft). I'd heavily recommend Nitrox! On every one of my trips I've seen mantas and sharks, etc. For whale sharks you either need to be lucky or be at the right season in the right atoll.
I would never travel there for just a week. 2 weeks is the most common trip duration for people from Europe.
Flying to the Maldives is a different problem from the USA. From the west coast you probably consider Singapore Airlines. A very good carrier, however you will arrive around midnight at the Maldives and leave at 2am or so. If you consider visiting an atoll that requires a flight with a water plane, you have to stay overnight at the airport or at the captial, losing 2 travel days. The other options is Emirates via Dubai, which can get you there in the morning (perfect) and you can fly back in the morning or evening, depending on you trip plans. I would pick them, I've flown both (in Business or First) they are good.
From the westcoast you either travel via Europe (e.g. via London or Frankfurt) or via the middle east (Qatar, Dubai). Connection times can be tricky and tacke vacation time away, Qatar airways is probably the best choice, Emirates also a good option. Via Europe probably only makes sense if you collect miles with a certain airline.
Feel free to ask me for more details.