Most of the really bad stuf has come post Commodore days, but in no particular order I'd have to say:
AGA being rushed. Most of the enhanced functionality it offers isnt even usable, or if it is compromises to the point of redundancy are in place. 32 and/or 64 pixel wide sprites are available for example, couldve been quite useful, but to use those modes screen must be shrunk and only 1 or 2 (no absolute rule, but as a general rule of thumb) are placable on the screen, the rest can only be used outside of the physical display... significant arcade gameing power, you just cant see it. The Amiga was for the most part so far behind by this time that getting AGA right was more important than having a system that on paper was on par with the graphics of other systems at the time, even if it took a while longer.
Akiko: I strongly believe that akiko shouldve been substituted for a small amount of fast ram (if trying to maintain a certain price point, but ideally both). The speed increase the system wouldve seen as a result wouldve been similar to what akiko could generate, but it also could be used for things other than chunky to planar conversions, and the speed wouldve been system wide. Would have resulted in a more balanced, and in the majority of cases, more powerful system.
And no.3 is a personal one.... me letting my friends try out the Settlers demo that came on one of the CU Amiga cover disks...... never before had my Amiga been so thoroughly hijacked
