I was not impressed by the i432 architecture. Like the Multibus, it seemed to be trying to be very fancy, but with no elegance or taste. The result was an architecture that... um... might possibly have worked. It's still an ugly, tasteless architecture, though.
The i432 was well before my time, so it's hard to account for the privilege of hindsight, but I found myself looking in horror at most of its design. Hardware needs to account for the fact it's ultimately a piece of physics, and the i432 dismissed this completely.
It's a real shame because the failure of old innovative architectures—faults ultimately down to poor and complex designs—have burned people enough that few people dare to try again. For all its flaws and forever-vaporware status, the Mill shows that you can make an architecture much safer without paying extra as long as you do things with principle.
You must be thinking about Multibus II. The original Multibus (IEEE 796) was very basic. Historical note, the DSP satellite (NORAD missile warning) ground network ran on Multibus based systems from 1988 until 2005.
It's still an ugly, tasteless architecture, though.
That is a bit odd thing to say about it, considering that many of the goals are being resurrected these days because its become clear that the RISC/UNIX model is insufficient for modern computing. Sure they may be "pretty" and KISS, but they quickly end up being polluted by ugly hacks to make them both perform well and more recently have layers of cruft added for security purposes. You need look no further than aarch64, particularly the 8.x supplements, or the ARM CHERI efforts to see this in action.
