Bravo is generally good to excellent on the ball - not in the same class as Ederson though.
At the same time, for whatever reason, Bravo is a shadow of the keeper he was at Barca - errors in judgement while in goal occur nearly every match and sometimes these mistakes lead to goals for the opposition.
Still - are we likely to attract and retain a better backup keeper? - maybe we could buy a quality goal-saver with decent on-the-ball skills who is past his prime and is willing to accept the backup role. But a quality backup/replacement to Fernandinho is far more important; and we could use a right back who poses more offensive threat than the excellent Walker in games where we simply need to break down packed defenses; in other words, buying a backup keeper seems far down in our priority.