Got to do some toon creation last night.  I have a lvl 50 (republic) Zabrak and a lvl 50 cyborg.

Cyborg

As expected, if you unlock cyborg, you get access to all the cybernetics in game.  The slider starts with the agent ones and works its way through to the trooper ones.  In the end there are 60+ options, but there might be some duplicates.

However, character creation is a bit tough without slider labels:

Hopefully that got fixed last night in the patch.

Zabrak

As you know, Zabraks can already be all the classes in both factions.  However, Republic Zabrak and Empire Zabrak are considered two different species for character creation purposes.  Getting to 50 with a republic zabrak unlocks “Empire Zabrak” for republic toons and “republic zabrak” for empire toons.

So you can’t mix and match the options (for example, the empire red skin tones with a republic tattoo).  I was kinda disappointed that I couldn’t get the badass tattoos of the empire side without those gross red-ringed eyes.