Crafting a flight model

As I peruse the last 3 editions of the SDK (not counting the 3 within-release versions this time), I am struck by the lack of information and tools on how to craft an accurate flight model from scratch. In a flight simulator, it is of equal or greater importance that a developer of add-ons be able to construct a good flight model. Very central to the whole idea of a flight simulator is, well, flight!

We've seen a great deal of attention to modeling the environment in which flight happens and we've seen the least amount of attention to providence of tools for accurate flight modeling.

ACES, please focus attention on this aspect as we move forward. While many approaches exist now to create accurate flight models, they are kludgey and archaic in nature. For several years we relied on a kludge in the form of FSUIPC to accelerate the capabilities of 3rd party projects until, wisely, ACES joined the fray and gave us SimConnect. Now, please let's have a sensible approach to flight modeling.
The ESP SDK includes information on how to do this, the source file format for the airfile compiler and the compiler itself. It sure would be nice to see that all made available for FSX developers...

ESP looks very cool and I'd love to check it out - but the price is a bit steep (no, I don't have a MSDN subscription).