I used to be (and still am) one of the biggest Amiga fans anyone is likely to encounter, but I have to concede that the Amiga's graphics architecture was ergonomically terrible for the vast majority of dtp work. Most people found working in the only native resolution really suitable for dtp, interlaced 640x400, to be intolerable to look at for even mildly extended periods of time. Things were even worse in europe, with the lower 50/25ihz vertical scan rates. The non-interlaced modes otoh had too low of a vertical resolution and the pixels were far too oversquare or rectangular to render many fonts accurately.
It took far too long to come up with effective solutions for this, and the ones that did exist, like the A2024 grayscale square-ish megapixel pixel display, noninterlaced, were too late and had too many compromises.
The Amiga had an uphill battle against the head start mac enjoyed ( and seemed, to the casual observer, rather naturally suited to with its crisp black and white display) in DTP to begin with, and without a native laser printing, a good scanning solution, enforcdd UI consistency through quickdraw and most of all adobe, there was never a reasonable chance that it would seriously challenge Apple in that market.
The unsuitability of a very visibly interlaced display to fine detail black and white layout work insured it would never be tolerated by people who had to work with such tools 8 hours a day.
Totally agree about the absence of a pennies per unit midi port as being a damnable error on Commodore's part; likely one of the main reasons the non-pc market was fatally fragmented three ways instead of a possibly manageable two, and gifting the ST (which was in all other respects an admirable me-too effort at best), a lifeline by which wedge itself into the nascent multimedia production market, which really would have been better off entirely associated with one or two platforms rather than two/three.