In addition, arming asuka with a melee weapon is pointless currently, because the AT field isn't down yet.
Most probably, you have to be in melee to really counter the angel's AT-Field. And I doubt that two Evas will be enough for this. So Asuka will have to go close anyway. So we can give her a proper weapon.
And, although it is a minor thing, Asuka may feel better if she has "her own" weapon.
I agree with what you're saying, for a conventional angel. This is not a conventional angel.
There is no such thing like "a conventional angel".
They just aren't going to matter enough to be a decisive factor in this fight. If they were, we would have won 3 turns ago.
Until AT-Field (which is multilayered here) is at least partially lowered, any attack is useless.
Also while Asuka is not receptive much to Rei now, I think that her willingness to help Hikari still is stronger than her disdain for Rei.
[X] Crossing the Red Sea
-[X] Use any means to create a smokescreen, tell pilots to use radar/infravision/any mode that does not rely purely on sight.
-[X] Orders for Rei: Take advantage of the smokescreen, and disengage. Go and assist Asuka with helping Hikari. Bring the naginata for Asuka if possible. If Asuka complains remind her that Hikari's safety is more important than interpersonal conflicts. Asuka knows this, she dived after Hikari. After helping them, attack Zophiel from range.
-[X] Orders for Asuka: Help Hikari to get out from the acid. After stabilizing the situation, take the naginata from Rei, and attack Zophiel in melee. Dispel AT Field, and kill the bastard.
-[X] Orders for Shinji: Continue fight in melee. If Zophiel tries to follow/attack the other pilots, prevent this by any means short of suicide. Dispel AT Field, and kill the bastard.
-[X] Orders for Hikari: Attack from range after she is out of the acid bath. Try to placate Asuka if necessary.
IIRC from episode 14, Evas have alternative modes of vision. Also, I am willing to give Asuka the benefit of the doubt and assume she intends to help Hikari, not to do something stupid.