All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
First of all, the Hadith to which you referred to in the question was reported by Muslim in his Sahih, and it was mentioned in the context of an answer to a question from 'Amr ibn al-'As and he [the Prophet] did not initiate to inform about it in the first place [he was asked and he answered the question].
Secondly, the Prophet loved all his wives, but he loved ‘Aa’ishah more than others, and they [his wives] know that he is not held accountable for this love and he does not have to feel the same thing with all his other wives because this is a matter of the heart and no one can control it except Allah, but he is ordered to do justice between them in actions, and this is a matter of consensus among scholars, as An-Nawawi said in his commentary on Sahih Muslim.
The Prophet used to be just between them in these actions, to the extent that if he wanted to travel, he would draw lots among them, and whoever the lot was on her name, she would go out with him in travel.
Secondly, in general, it may be wise for the husband not to mention that one of his wives is more beloved to him lest he provokes their feelings, but when it comes to the Messenger of Allah then this is another matter, as he is the example, he may tell that so that people can follow his example and love the one he loves, and this is one of the greatest acts of getting closer to Allah. In the same Hadith, the Prophet informed that Abu Bakr was the most beloved to him among men. In some other Hadiths, he mentioned his love for the Ansar, so it cannot be said that this may bring sadness to the rest of his companions.
With regard to what you referred to at the end of the question regarding the Companions choosing the day when ‘Aa’ishah is with the Prophet to gift him, then this is confirmed in a Hadith reported by Al-Bukhari and Muslim. This is an action by the Companions and it was not his choice; this is clear and the scholars have pointed out to this fact.
Allah knows best.