Is it possible that Ford put all of it's cards on the table too soon with the 2005 Mustang style?

There is no doubt that the latest incarnation is awesome. Like the first Mustang in '64, the current body has resurected the "Pony Car" market with GM and Dodge again playing catch up.
The problem is that the Mustang hit a home run on it's first at bat. Leaving little room to change the body without losing the classic inspired look.
When Challenger and Camaro debut in the next 24 months, the current Stang will be 5 years old, and frankly, tired.
Much like seeing a magician. The act is cool the first few times. Then its a case of what have you done for me lately?

So, my question is, Did FOMOCO make the Mustang TOO good? Any major deviation will start the slippery slope of undoing the design.
Perhaps the Mustang should have been a slower (3-5 year) design change process. With each new year bringing her closer to what we have now. Keeping buyers interested and wanting to trade or purchase the next version.

I'm afraid what we may see is the repeat of the 1979-1993 (you can really say '79-2004) overuse of a chasis.