I owned both a tg16 and TurboDuo, amazing systems. The cdrom definetly made for some great games like Ys Book 1&2, Ys 3, Ys 4 (with the nightwolf translation bin/que rewrite), Dracula X, Gate of Thunder, Lords of Thunder, Street Fighter and Super Street Fighter (yes it was a hucard but still amazing). The 5 player games like the TV Sports games were a huge hit with all my friends, we'd play for hours together.
The tg16 did amazing in Japan and the Asia market (PCE or PC Engine there) , so much so I can't call it a failure anywhere here but the states.
The follow up system the Supergrafx really crashed and burned everywhere getting only 3 titles, but Super Ghouls and Ghosts was a dead ringer for the arcade version.
Sega Saturn crashed and burned hard everywhere.
Sega Dreamcast did extremely well in the states (even was selling better in the US than the PS2) but so poorly in Japan and the rest of the Asia market Sega pulled the plug on it before they got bought out by Sammy (Japanese company that made games and roulette wheels). Phantasy Star Online was a blast.
The 3D0 was a fun unit with some great games. I think the reason for the crash and burn there was more due to no ESRB ratings system yet and the overflow of adult games really removing it from something Parents wanted to get their kids. You'd walk into an EB Games and find a racing game like Crash N Burn right next to an interactive porn flick like Real Plumbers don't wear Ties. I saw many a parent yank their kids back from the 3D0 games when they saw what was over there.
Can I safely say Digital Dreamware was probably the predecessor to Rez? It seemed more like some kind of electronic acid trip than a game but still.... I've got stacks of 3D0 games and a console I still mess with from time to time, the video cut scenes definitely made it worth playing over and over.
Putting the ram in the cartridge with the game instead of in the system killed the NeoGeo as a home unit, but boy was it bad-ass for the day. Most parents can get past a big initial cost for a console but when every game is another $200 a pop on top of that its a no go.
As an arcade unit though the NeoGeo was amazing and there always seemed to be at least one in every arcade I went into. Hell they're STILL in arcades this day (when you find arcades).
NeoGeo CD was a major crash and burn because there wasn't enough ram, they put a 1x cdrom on it, and the games were programed to interact with the amount of ram in cartridge not in system so everything choked and stuttered because no one rewrote the games to optimize them for the system.
If I'm not mistaken, I believe the FM Towns was the first cdrom system, but before it could come to the States the tg16 pretty much killed it.
I'll tell you though the one huge mistake that was made that switched the entire face of the home console, Nintendo having Sony make a 32 bit cdrom add on for the SNES on mostly Sony's dime with the understanding Sony would have control of licensing those lines of games then dumping them the day before the launch (and with the observed 32x add on for the Genesis tanking the way it did can't say I blamed them). Sony was beyond pissed and with a little redesign released the units as the first PlayStation. Nintendo stuck to cartridges and released the N64 and they've barely been holding in the console market since, innovation with their controllers is their single selling point anymore.