1. SMS 2
2. NES 2
3. Mega Drive 2
All 80's systems designed in Japan that look faaaar worse than the TurboGrafx-16, even with the CD-ROM attached. The SMS2 is just downright hideous! The Turbo looks sleek, like a sports car. I'm not sure why the Turbo gets so much hate. It was definitely designed in Japan. It is a near carbon copy of the PC Engine molding, just longer.
I like the NES2. I also kind of like the Genesis 2 (although not as much as the original, and certainly NOT the Sega CD2). Obviously the SMS2 is just a terrible, and terribly cheap, looking POS.
What exactly makes you think these designs were from Japan? I have little insight to the way the product design works and for sure these sorts of things were outsourced all over the place. Sega and Nintendo had a very international presence back then, I wouldn't be surprised if the SMS/Genisis/NES2s were from like...Frog Design, or IBM or someplace. Was the SMS2 even released in Japan?
The TG-16 does indeed look like a stretched PCE, and why it is stretched, why the internals are all full of kit instead of just air...did we ever figure that out? Either way, I think you are right that that NEC probably did do that design, but why is it big?
It certainly doesn't look like a sports car. One of the cardinal rules of sports car design is that it shouldn't be any bigger than it absolutely has to be. Lotus 7, Mazda Miata, Alpha Spyder. The TG-16 is much more like a Pontiac Aztek, esspecially with that stupid hollow cover on the back. And the CDROM2 set-up for it...what the hell? Could it be any stupider?