Besides works versus grace and indulgences, what were the external practices of the Catholics that offended so many reformers?
score:9
Accepted answer
Book IV of Calvin's Institutes of the Christian Religion deals with many objections to the practices of the Catholic Chruch, frequently with rather harsh language.
The claim that the Roman church is the only church (Chap II.2)
The communion as practiced by Catholics is idolatry: "The foulest sacrilege has been introduced in the place of the Lord's Supper."
Reliance on Church teaching instead of the Bible (Chap II.4): "Paul reminds us that the church was founded not upon men's judgements, not upon priesthoods, but upon the teaching of apostles and prophets [Eph 2:20]."
Elders should be elected (Chap II.15). Reference is made to Acts 14:23, which seems to have a disputed translation, but also to the practices of the early churches.
Bishops should not have ostentation or pomp (Chap IV.7)
Examinations of church leaders was not done, or if done was not based on ability to preach. (Chap V.1)
The Church did not reject interference by princes (Chap V.3)
Church titles are conferred without regard to need (Chap V.7)