Just a general question… Why is it that a plane and avionics package (in this case Cirrus and Arnav) are bundled in such a way as to be required…?
It seems to me the future of GA is one where people have more freedom in customizing their planes at the source… assuming it can be done cost wise…
It’s not quite as bad as that. The issue is that Cirrus has gotten certification with the avionics as delivered that basically guarantees that they work in the airplane (and aren’t affected by some part of the airframe, and vice versa). Any avionics you install will require some form of certification; in the aftermarket you’d have to install TSOed avionics and get a 337 signoff from the FAA in order to be legal (relatively easy with avionics). If the avionics were required for IFR, you’d need a flight test signoff as well.
For Cirrus to offer other avionics from the factory would presumably mean that they’d have to spend the time and money to get their TC amended.
As long as the avionics are not required for certification (including IFR use) you could simply yank them and still be legal (so if you’d rather see a big hole than the ARNAV you can pull it any time you like.) Putting anything else into the big hole would require a 337.
There are also production cost issues–wiring harnesses are labor-intensive to make, and the more options you throw in, the higher the production costs go. In the olden days you could get a la carte avionics from a menu (though there weren’t many choices back then); even Cessna figured out that this was not cost-effective.