For some reason, some of the early 209's did not have the "hook" added to them and the boat would porpose as you stated. A good friend had this issue and you could get the boat to settle down simply by shifting some weight to the front of the boat(bow)....we diagnosed it by getting the boat to the point of porpose and walking 3 guys from the back of the boat to the bow and it calmed down. Long story short, check with your local dealer and talke to them about adding the "hook" (a small downturn in the fiberglass that is added to the rear of the hull, creating upward lift of the rear of the boat), and you should see your problem resolved. Also, by doing this, the ski wake will improve but keep in mind the the wake of any boat can be poor at slower speeds and if you are not on edge when cutting thru it (pending line length of course.)
Hope this helps and congrats on the new boat, you will love it once you get the issue resolved.