What is the ruling on a Muslim supplicating with whatever he wishes while sitting between the two prostrations, and is its virtue greater, or supplicating after bowing?

The prescribed action after rising from rukūʿ (bowing) is dhikr (remembrance of Allah) and thanāʾ (praise of Allah). Between the two prostrations (sujūd), it is duʿāʾ (supplication) and asking [of Allah]. The category of Qur’an recitation is preferred over adhkār (plural of dhikr), and adhkār are preferred over duʿāʾ. The best dhikr after reciting the Qur’an is that which involves praising Allah, because it takes precedence over a servant's asking for himself, and praise encompasses the intent of supplication. An action that is less preferred may become superior if it is coupled with the virtue of a specific time or place. Dhikr and duʿāʾ are preferred over Qur’an recitation during rukūʿ and sujūd due to the prohibition of reciting [Qur’an] in them. The best action in prayer is to perform recitation, dhikr, and duʿāʾ, each in its designated place. Duʿāʾ is permissible during qiyām (standing), rukūʿ, and between the two prostrations, but it is best to perform each dhikr in its authentically reported place, both in type and wording.