Uhmp... That's an interesting oppinion. The way the IEC bus is implemented on the C= makes it very slow and complex to interface. Building a network interface for the IEC bus would first require a compatible controller to be built to emulate a file device. Although this is theoretically possible it would in the end render a netowork device so slow that it would be useless without some kind of custom IEC protocol (similar to a "FastLoader"). Further on it would be pure pain to program for it using sequential access.
IMHO the Userport is device-wise closer to a Network interface than the IEC bus. Although the hardware and software required is still too complex for easy and efficient use, viewed from a software perspective.
The Cartridge port has exactly what is needed for a Network device (direct memory mapped access) and is in its design intended for peripheral expansion. In other words: adding hardware capabilities to the C= such as a Netowork interface.
Of course the problem is that we want many such devices hooked up simultaneously, but it seems to me that most of those needs can now be solved either by port expansion or "all-in-one" cards like the 1541UE, MMC Replay, etc.
That said, I would still be the first in line to support a IEC or Userport enabled Network device project
