AMIGA is and was good machine.
Look back at game like SWORD OF SODAN, HYBRIS, or XENON
These 512K memory and the 68000@7 Mhz was more than fast enough for them.
These games really made good use of the capabilites of OCS chipset with 512 KB.
Later AMIGA models were rarely used fully.
2MB Chipmemory was common even with later ECS AMIGA.
Now imagine how nice and smooth a SWORD OF SODAN for 2 MB with 4 times the background images and the sprite animation would have looked?
It certainly would have looked breathtaking.
Or imagine a good STREET FIGHTHER port making maximum use of 2 MB Chipmem.
The AGA machines had 2 MB chipmem, 256 colors and faster CPU.
Regarding Audio:
For games 8bit audio samples with own volume per channel is great.
With own volume per sample this give great sound effects for games.
In theory more than 4 channels would have made coding easier.
But on the other hand a 68020 with fast-mem has more than enough computing power to mix many channels together in real time.
Imagine if games would have been designed for AGA machines with 2 MB fast and 2 MB chip.
The typical 2D game has enough free CPU to allow real time mixing of 8 channels modules.
So you can imagine now a SWORD OF SODAN with 256 colors,4 times the animation frames and 8 channel audio sound in the background.
Or imagine a 2D Game like XENON in 256 colors, with 4 times as many sprite animations, and super mixed sound.
If games would have been designed for AGA Amigas + fastmem then these type of games would have been possible.