I don't think Witcher 3 is going to be like the Witcher 2 as far as the Enhanced Edition goes. The team that is working on the Witcher 3 is much larger compared to the team that worked on the Witcher 2, and they are more experienced this time around. Also CDPR is now an established company that is financially stronger and can take more risks without the fear of going bankrupt at any minute. In the case of Witcher 2 the team even had to cut out a whole area out of the final game, because they did not have enough time and resources to finish it. And the final chapter was also very short, although they did the best they could. After they released the game, they used the additional time and some of the money from Witcher 2 to add intro, outro, transitional cutscenes between areas, and some additional missions to make the final chapter longer. So they basically went back and fixed what they couldn't do before, because they were out of resources and time. For Witcher 3 they have had enough time to finish the game, and they even delayed the game to make sure they get to make the final version as "Enhanced" as they can. I think for Witcher 3 we are going to see additional missions that take place after the game ends released as additional content after the game is released. I hope that CDPR releases some DLC missions where we get to play as Ciri after Geralt's story concludes.
The difference between CDPR and companies like Ubisoft and EA is that, Ubi and EA plan the DLCs and season passes before the game is even released to make more money. If you know your game is not FINISHED, and there has to be DLCs that you are going to charge for, then they need to be included in the game. A finished game should cost 59.99$, so if you are going to add story content and charge people for it then you are cheating them. In the case of CDPR, they listen to fans and try to improve what the game lacks, and even add some additional missions for free just out of love for their fans.
That's why I respect and love CDPR so much.