Following the radiation leak, Data takes both the torpedoes and phasers offline. To detect the Romulans, he orders just the phasers back online and not the torpedoes. But then he fires torpedoes and not phasers, before ordering the phasers back offline.
At first Picard says his fleet has 20 starships in it, and later on it's said that the fleet has 23 ships in it, it's possible that a few more ships were able to join the fleet after the initial briefing. Yet the tactical display on the Enterprise shows only 17 ships in the fleet, and the Excalibur appears on the display as being part of the net, even though Picard ordered it to fall back and appear as if it's having engine trouble.
In the time that elapsed between the production of Redemption (1991) and Redemption II, the Enterprise sets went through a significant transformation, particularly with the Observation Lounge receiving new lighting and a new wall replacing the display of star ships. No explanation is offered in the story to explain these changes. Where it could it be assumed with past upgrades of the set that considerable time had passed since the previous adventure, these changes took place between parts I and II of the same story.
However, from what Gowron says, at least six weeks elapses between parts one and two, more than enough time for the Enterprise to undergo a minor refit, which would explain the changes made.
At the end of Redemption (1991), it was stated that Worf was to be tactical officer aboard Gowron's ship, but here he appears serving aboard Kurn's ship, the IKS Hegh'ta.
The reason O'Brien appears to be wearing the rank insignia of a lieutenant, even though he was a non-commissioned officer with the rank of chief petty officer at the time, is because at the time Starfleet did not have separate rank insignia for enlisted personnel. Plus producer Ronald D. Moore stated once in an interview that at first O'Brien was just meant to be a minor background character so the writers didn't worry much about what his actual rank was.
Picard actually orders only one ship to fall back and pretend to have engine trouble, the U.S.S. Excalibur. The U.S.S. Akagi and the U.S.S. Hornet were supposed to pretend to attempt to fill in the gap left by the Excalibur.
The Romulans were almost certainly monitoring the task force's communications, in which case Commander Sela would know who is commanding which ship. Plus Data's positronic neural network emits a unique signature, detectable from several light years away, so even if they weren't able to monitor the fleet's communications their sensors would have detected Data aboard the U.S.S. Sutherland.
When Worf tries to stop the fight when a Klingon challenges Gowron, Gowron is able to kill that Klingon. But while the dead Klingon is on the floor, the actor is obviously not able to hold his breath from the struggle with Gowron.
Maybe Starfleet has given up on this one specific naval tradition but a captain who is given temporary command over a fleet of several ships is traditionally referred to as "commodore".
When the Romulans disrupt the tachyon net, Data reports that the net is no longer effective in the range of 10 million kilometers around his ship. At the same moment, a display on the Enterprise shows this hole in the net being almost half the size of the entire net. This makes the entire net about 40 million kilometers wide, which is vanishingly small compared to interstellar distances. The Romulans never had to worry about passing through the net, as it would have taken them only seconds to go around it.
While the Hegh'ta is being attacked at the beginning of the episode, well after Worf tells Kurn that "the aft shields are gone," the attacking ships are shown hitting the Hegh'ta from behind with disruptor fire, which is dissipated by the aft shields that glow green with every hit.
When the Romulan Commander Sela is speaking to her fellow officer about tactics, she says "We will attack her - the ship with the android commanding it." She would have had no way to know who was in command of that ship.
When Picard is talking to Guinan about the Enterprise C, he mentions it was lost 23 years ago. Later, when talking to Sela about the Enterprise C, he says it was destroyed 24 years ago.
Chief Petty Officer Miles O'Brien is shown with a lieutenant's insignia.
Picard commands Data to select a group of experienced commanding officers to augment the ships. Data then asks Picard why he can't command a ship while he has 26 years of experience. Moments later Captain Picard gives Data the star ship Sutherland because it needs a captain. When Data sets foot on the Sutherland, he introduces himself to Lt. Commander Christopher Hobson. Hobson seems to have the right experience to command a ship.
When Data orders the phasers and torpedos taken offline, thus exposing his crew to radiation, he feigns anger at Lt. Cmdr. Hobson for questioning the order. In the same amount of time (or less) he spends "arguing" with Hobson he could as easily have explained his order and the rationale. That is what a competent officer would do.