I'm hoping the 'neutrals' won't require very specific playthroughs in order to keep the MC neutral. Otherwise it'll just be an on-rails story for them. Having to keep score, for example: "I need to make 10 'selfless' and 10 'selfish' choices to keep myself neutral" would just be forcing on-rails paths.Like you said, we're too early in. I think down the road, the MC will be presented with larger moral dilemmas and the "selfish" option will be more like a lawyer known as a shark, doing anything to win, crossing ethical lines, etc. We've seen this out of Aurora already as she used her femininity in order to get her hands on information she wouldn't have otherwise for the mock trial. A selfless MC probably wouldn't go that route and eventually will be in a situation where Aurora just isn't impressed anymore.
Neutral, in my opinion, should be open to any alignment as they fit in between both. Perhaps if you take a particularly "selfish" decision point, they may express displeasure or question it, but not lock out their path. Or if you take a particularly 'selfless' decision point, they may ask about why you went that way. As there is a time and place for both in different scenarios.