Regarding the PC Engine. It would be a big shame if an Engine PC is made but does not come with a CDRom drive included, or at least, a USB port to which one can connect an external one.
Now for the Gen/MD, one could argue that the CD is niche and isn't really needed to enjoy the majority of its library. But the PCE/TG16 without the CD is practically pointless. :/ (Hucards vs CDs in my library are at best 1/10th of the CD games.)