Well we know combat droids are in the works, hopefully it will be Droideka droids or IG-88 bounty hunter types (which would actually be a better fit for the timeline of the game).
As for unruley pets, I like the idea but perhaps only if the master doesnt feed them or treats them poorly, stuff like that.
There are personality chips for droids in the game already, one of which is the sarcastic type droid chip. Although it is pretty tamed down sarcasm.. but still the idea is there. When you go to teach it commands it replies with "What do YOU want?".. etc. However, I would like the droids to be more NPC, chatting away in the background while you have them out. This brings up spam issues however.