The Power is meant for more aggressive riding positions. I know some posters here like them even though they ride more upright, but in general it was designed to allow riders to be more comfortable when getting low. I got my first one during a Retul fitting at a Specialized dealer, and my fitter mentioned that people who like the Power often like it tilted down about 3 degrees. If you have too much weight on your saddle vs. other contact points, consider whether your saddle is too low or your hips may not be rotated enough so that you're leaning backward.
Specialized also has upgraded versions of the Power, such as Elaston and Mimic, that offer different padding in different places. I ditched my original Power and now have both, and while I haven't noticed Elaston being much of an upgrade, the Mimic has been just about perfect. If the Power shape works for you, and it's just the firmness that you can't get used to, you could try those options.