Is Starflight for both versions/is everyone aware of how different they are?
Isn't the GEN version basically just the first game with slightly higher color range and different interface, or am I mistaken in that? I know that's the case in the Amiga/ST ports, and for the C64 port, I have nooooo idea.
While I'd say maybe focus on one but make sure you play the other just for a bit to get a feel for the most immediate differences - Starfight is also trailing so I guess we'll see if it's even necessary.
Out of all of these, I'd have to vote for Legend of the River King---in no small part because I remember wanting to play it when I was younger. Also, it's available on the 3DS eShop---and while I'm a sucker for obscurity, I'm also a fool for accessibility.