Only the graphics are better than the original (of course). I didn't like the story changes which are mostly simplyfing. Lucas Bertones missions are missing for example. The game controls are horrible now. The atmosphere during during car driving in the city is also much worse. The race in classic mode seems even harder to win than the race in the original game (both games with mouse and keyboard). Probably it is much easier with the stick but I don't care. I was only able to win the race in hard mode and if you don't win the race you can't complete the game in that mode.
The game is certainly very big and a huge effort but it's not as good as Witcher 1, except for the combat system. The combat system in Witcher 1 is pathetic and the game is therefore too easy on highest difficulty but atmosphere, story and music are better. Of course Witcher 3 has better graphics but this is not that important for me. Other weaknesses of Witcher 3: -You can steal almost everything in front of the NPC's. This is just ridiculous. -Collecting items is quite pointless since you have always plenty of crowns anyway. Far too many items are useless.