...imagine a custom Axe block builder IDE and custom blocks exchange, kind of like Steam Workshop...
Of course Cliff ain't gonna let us peanut-gallery hackers/developers willy-nilly into the FAS ecosystem. Imagine the support calls and headaches.
I don't think the "write your own custom blocks" idea would involve "letting peanut-gallery hackers/developers willy-nilly into the FAS ecosystem." (What I mean is: That phrasing makes it sound unsafe, like it was brain-surgery done by a million monkeys with code-editors. But I don't see why it should
be unsafe.)
I can envision the kind of IDE you described. I think it would be, for the innards of a Block, much like what the Grid is, for the innards of a Preset. If letting a user design his own preset isn't unsafe to the ecosystem, I don't see why letting a user design a block to put INTO the preset would be.
If you look in the FAS manuals at how each block is described, and at the signal flow diagrams which describe what each block does, you're basically looking at a
very rough wireframe of how you'd need the IDE to work.
If this ever happens, I think it'd take the form of an Axe-Edit-like tool, which allowed a user to build a new block out of the types of "sub-block components" that all the existing blocks are made from, and wire them together with feedbacks, etc.
Once assembled in the tool, the newly-defined block would be exported into a file format which could then be uploaded into the Axe III. Since the current blocks in the Axe III are arranged into an "Inventory" and categorized into different block types (with a maximum number of instances of each type available on the Grid at any time), I suspect the firmware would need to be modified to allow a new "Custom (CST)" block type, with an inventory of four CST block-instances placeable on the grid.
(I'm not wedded to the above-proposed details; I'm just trying to float some possible implementations of the idea. If we can flesh it out enough, maybe we can transform it into a do-able "WISH" item.)
I'm pretty sure Cliff would substantially benefit, if he could provide us the ability to invent our own custom block types in this way. Specifically: He would never again have to hear people asking for a Klon or a FreqOut or some other missing block type. He could just answer, "Hey, you have the custom-block designer tool. Go build it yourself and stop buggin' me."