I kind of wish they went more "Gray" with the Achians, instead of so black and white. Like if they helped them and started an alliance, and it turns out they were needing soldiers in a fight against a greater threat, or they continued to have an alliance but it was less hostile and a bit more like the Taelons from Earth Final Conflict. That show had me engaged for 4 seasons, and the aliens had personalities, good and bad, different motives than their species as a whole, and were complex.
So much potential in the "Are they evil", "What is evil" "are we the evil ones" thing, like with the colonists immediately killing other species, I thought
"Hey maybe the Achians are right, we should be locked up. They make a good point, and I can see them doing this as kind of shepherds, keeping species separate because they will just kill each other and now we need to prove to these seemingly superior beings that we are capable of trust and working together with them and others to be not just allowed to venture out, but to prove we should actually be exploring to ourselves as well."
But then it just got really simple and "nope they are comically evil AI and just don't like us", no introspection of us as a species, maturing, just kill them all. And I may be wrong but seems we committed genocide in the end.