Well in the original script Oola's character was far more developed and she had a lot more to do. She actually escapes with Luke and the others and ends up joining the alliance as a dancer to boost morale or something. It would have been cool to see that but it would have probably meant sacrificing all the shots of Leia in her gold bikini, so even though I prefer Oola I don't think phasing Leia out as slave would have been smart.
Also Oola has been confirmed as one of the characters that will be on the Star Wars Live-Action show if it's ever made.The new series is focusing on minor characters and telling their stories so I'm looking forward to that. Unfortunately right now the show is kinda of on the back-burner and there's speculation about whether it will ever be made or not. I'm keeping my fingers crossed though.