The traditional breviary would be something like the one on breviary.net (warning as to the ownership) though there are certain modifications between the version there and the 1961 breviary used by the FSSP, ICRSS, etc. I’ve seen a couple of Latin-English editions that pop up on ebay but they are always expensive and snapped up.
As to the flaws, there are criticisms. Notably one is the criticism of the omission of the 3 imprecatory psalms and verses from the cursus (cf. GILH no 131). You might have noticed one example of this omission in Evening Prayer on Sundays- psalm 109/110 omits verse 6.
Some also are not endeared to the idea of the 4 week cursus as opposed to the former weekly one. Then also reduced psalms, on Sundays and major feasts, fewer lessons from the Fathers, and other things, big and small, and numerous responsories. In some cases, the connection with the Mass was very prominent- like a Gospel Homily on the days Gospel. Some people don’t appreciate the idea that the lives of the Saints were consigned to the small notes under each saint in the Liturgia Horarum.
One thing I personally regret the loss of, are the distinctions of the Office of the Dead- the omission of the versicles, saying “Eternal rest grant unto them…” at the end of the psalm, and things like that. Also the loss of the distinctive Office of the Holy Week particularly the Triduum- they are no longer that different from other Offices in the ear. These small differences did highlight particular times in the Liturgical Year and curiously, were quite apt in matching the “mood” at that time (at least, tats what I felt).