I am reaching the point in the game I haven't reached before. I haven't researched Psionics, Destroyer, Heavy Plasma, or any techs after that yet, so I don't know what they do.
I know Psioics is for mind control(Sectoid Leader Units), I know Terror Ship comes after Destroyer, and Heavy Plasma leads to Blaster Launchers and better ship weapons.
Psionics are for mind control AND panic attacks, and can be used by sectoid leaders/commanders and all ranks of ethereals. Also, unlike to original game, ethereals come with all ranks, not just leaders and commanders. You find commanders on board terror ships and battleships with a gear level of "Good" and during alien base defense I think. Heavy plasma is fun.
Humans get psionics by interrogating psi-capable aliens, so as long as he doesn't capture any live ones you're okay. Also, don't let blaster launchers fool you when you get them, I think they canned the waypoint system. That, or it's some ambiguous key I don't know about. I almost shot my ethereal medic in the back when my ethereal commander fired his blaster launcher in Necro's base, thinking I would set the waypoint but instead just shooting it straight into the floor outside the hangar. Strangely enough, the medic was unharmed.
Little bit of advice: mutons and ethereals require double the food of other races. A ship with 5 mutons/ethereals on board will consume 10 food a mission. I could understand it with mutons, being huge brutes, but it's probably for balance purposes when it comes to ethereals because they're physically retarded and have little energy-burning processes to begin with.
So - your starter base can produce any race, but further bases can only produce the type they were started by, right? And it can produce their terror companions, I assume?
It seems that way. I had races up to Snakemen when I was playing against Necro and I sent out a mothership loaded with sectoids. When the base was built, I could only breed sectoids and cyberdiscs.
Also, GOOD GOD MAN. Research large ship construction, or something! They're more efficient. 4 tiles of facility = 5 construction docks. The same goes for large breeding.
Oh, and about snakemen, they are SLOW ASS and have bullshit reaction scores but they can shoot surprisingly accurately.