I'm playing through the Genny version now, and then I'm going to go back to the TG version. I'm playing the fighter, and while his sprite is taller it actually looks less detailed than the TG version. The Genny's music is closer to the arcade, but that's solely by virtue of the FM synth. I'm still at a loss as to why the PCE hardware design didn't incorporate a little additional FM synth considering the Famicom Disk Drive did.
The level graphics are a little smoother, in that they flow a little better, but the color counts are just so low. The TG version looks more tiled, but the GEN version looks so bland. The lack of colors make all the larger sprites, for characters and enemies, look less detailed rather than more.