This is a really big improvement indeed. Because they didn't see any other way than cutting the power by some rate last season to get ahead of serious issues. But now they are claiming that there is no need anymore. I really can't trust them completely yet as we are talking about Ferrari. We need to see them racing without the same problems for some weeks to be convinced about them. Then I can say my favourite for the championship will be Ferrari this time.
It won't just be the engine, I think Ferrari's chassis will be improved compared to last year, it's just a feeling that Ferrari will start the season the strongest. Mercedes and Red Bull will also have improved their engine/powertrain. The question is, like last year, will Ferrari have an advantage and can they eliminate their own mistakes?
I think we can watch a similar start to the one in the previous season. Ferrari would put on a good show with a fast car for a couple of races first. But the most important points is to be consistent of course.
I'm very hopeful that they won't be having durability problems again. On the other hand Mercedes also started to seem frightening to me. Even if Ferrari start strongly and fight at the same level with Red Bull, Mercedes also seem likely to join this competition. Mercedes also have introduced their car and it looks like they are back to black again. W14 might be another loved car for Mercedes if they have solved the biggest issues and gained some more power.