Well I remember my 386 having 16 bit sound, a MIDI soundcard, VGA graphics, and it was expandible to 16MB of RAM without buying expensive addons. I do own a 1200 BTW. My 386 (and Wolfenstien) are probably why the A1200 and Amiga itself died out fairly quickly.
From what you described of the Amiga One machine it sounds like a cheap X86 running linux would do the same job at a much smaller price tag (and allow the use of Openoffice and Firefox). Why pay more for less? The original Amigas were way ahead of other platforms in the Audio/Video/Paint areas, where does the AmigaOne/OS4 break new ground?
I have to admit that classic Amiga OS was pretty good with limited resources, sounds like OS 4 follows in that tradition. The thing is RAM and HD space is pretty cheap today, negating the need for an OS with a small footprint.