I tend to prefer the older design, because the lack of facial features is more mysterious, there is no expression of emotion that could clash with the player's expectations. (You're falling in a lava! Stop smiling!)
When I think of all the low-resolution game characters like this one, (first version), with focus on realistic body proportions, I remember mostly their athletic ability, and sometimes body language. "Faceless" character helps self-identification, IMO. (edit: Which might explain the popularity of ninja characters when I was young ?)
edit: I did play the original game on the CPC, but outside Spain, the protagonist was changed to a blocky, rigid, sexless space suit.