Higuain is better than Morata in my opinion but it will not change anything in Serie A even if the deal is concluded. Juventus was already dominating the Championship there during these last years and now that they got Cristiano added to their team chances for them to lose their domination is really slim.
Both Napoli,Roma and other contenders cannot compete with Juventus in Serie A and that is why this league has become boring to watch and also they are not performing well in Champions League either because of lack of competivity.
All of these can change next season with A.C. Milan as they are now owned by Elliot Advisors which is focused on bringing back Milan to its former glory again. Milan have a good roster to compete in Serie A but they are headed by the wrong manager under Gennaro Gattuso hopefully he gets sack by the end of this season and be replaced by a more experienced manager who can sign big names. Juventus is still the king in the league though but hopefully A.C. Milan can bring some big competition back to the league.