Ballblazer on the NES just seems to be badly done (that, or the NES likes working with sprite objects much more than arbitrary lines). Anybody remember 3D Worldrunner / Tobidase Daisakusen, and its sequel JJ? There's even some scaling in that one if I remember. But the main thing is that there's no reason for the game to be so jerky from side to side. Another possibility was that perhaps the NES hardware isn't normally suited to having two graphical planes moving independently of each other, but that doesn't seem to wash wash; Metal Storm and other games have parallax with actual textured backgrounds. This game's playfield might make it more complicated to render than the usual one-way scrolling of a two-lane arcade racer's highway, but still...man that's slow.
Xenophobe looking better on the 7800 is no surprise either considering that it's essentially a single-screen game that in its original arcade version had a deeper color palette and very detailed artwork - here the extra colors of the 7800 helps make the various gameplay items and the background stand out. It loses most of that detail in both of the console versions, but early Sunsoft's graphical "overhaul" of the NES version didn't help out any. Both ports are lousy games. The original isn't the greatest either.