Those 20+ non-Roman Churches believe in everything the Magisterium teaches and reject everything the Magisterium rejects on matters of Faith and Morals. Thus they believe in the Trinity, the Divinity of Christ, the Redemption, etc whilst rejecting the ordination of women, sexual activity outside of marriage, homosexuality and same-sex unions, contraception, abortion, euthanasia, etc. They have the same Seven Sacraments, essentially the same Liturgy differing only in externals and the same unity with the Pope.
This Vatican II Rite which you propose could never in a million years be in union with either the Roman Church or any of the Eastern and Oriental Uniate Churches, it would be just another Protestant church calling itself Catholic as the Episcopalians do.