Is excessive major and minor ablution before every prayer in Ramadan considered a mistake or an abundance of doubt?

The phrase "major ablution" is unknown in the terminology of the jurists. Ablution (wudu') is purification from minor ritual impurity, and ritual bathing (ghusl (definition)) is purification from major ritual impurity. If you mean renewing ablution before each prayer, then this is recommended by the majority of scholars. However, repeating ablution or ritual bathing before each prayer has no evidence for its legitimacy and should be avoided.