Give everyone a role in the big end-of-adventure battle. Especially if they're not combat-oriented characters.
This goes in the other direction too. Give the combat monsters something to do in the kindergarten class supervision scenes.
And yes, Wedge is played by a different actor here (Denis Lawson) than in his earlier scene (Colin Higgins). The story is that Higgins didn't learn his lines and fumbled through the scene in the briefing room, resulting in him being fired and Lawson being given the part for the remainder of the film as well as the two sequels. And they simply didn't bother refilming the briefing scene with Lawson.
Author note: We know the foreign language sentences in the comic are really badly translated. They are meant to be that way.
Transcript
Leia: Okay pilots, listen up. Approach from 90 degrees to the main weapon. That side's less defended.
Leia: Then you'll run the gauntlet across the surface to the vent. Our R2 unit is calculating the details for avoiding the point defence fire.
Luke: All pilots report in.
GM: Sally, take this note.
Red Ten: Rouge Dix, debout.
C-3PO: He said, "Red Ten, standing by."
Red Seven: Rojo Siete, de pie junto.
C-3PO: "Red seven, standing by."
Biggs: Red Three, standin' by, y'all.
Porkins: Coch Chwech, yn sefyll ger.
C-3PO: Red Six, also standing by.
Red Nine: Punane Üheksa, seisis.
C-3PO: Red Nine, ditto.
Wedge: Red Two, got your back.
C-3PO: Which means "standing by", right?
Red Eleven: Gorria Hamaika, eta zutik.
C-3PO: Red Eleven, take a wild guess.
Luke: I don't know what we'd do without you, 3PO.