Over in the TNG forum I've been revisiting TNG
and offering little reviews. While doing this I was struck by how many TNG episodes could have ben done as TOS particularly during the first three seasons.
So here's a little rundown of the ones I think could have worked.
“Encounter At Farpoint”
The Enterprise crew is put on trial for the crimes of humanity.
"Code Of Honor"
Uhura is abducted and Kirk must defer to an arrogant leader to negotiate her release.
"Angel One"
The Enterprise seeks survivors from a wrecked ship on a world ruled by women.
"The Arsenal Of Freedom"
While answering a distress beacon the Enterprise crew is beset by a world of ancient weapons.
"Symbiosis"
Kirk is caught between two disagreeing factions while trying to adhere to the Prime Directive.
“Conspiracy”
Kirk suspects starship and Starfleet personnel are being taken over by some unknown influence.
“The Child”
Uhura is impregnated by an alien entity.
“Where Silence Has Lease”
The Enterprise is trapped in an unknown void and the crew subjected to tests.
“Loud As A Whisper”
A deaf and mute mediator is assigned to arbitrate bewteen warring factions.
“Up The Long Ladder”
The Enterprise answers distress beacons from long lost colonists.
“The Survivors”
Two people are the lone survivors on a world devestated by an alien attack.
“Who Watches The Watchers”
Kirk seeks to minimize Federation contamination of a primitive culture.
“Booby Trap”
While investigating a derelict ship the Enterprise also becomes trapped.
“The Enemy”
Sulu’s survival depends upon working cooperatively with a Romulan officer.
“The Defector”
A Romulan officer seeks to defect with vital information.
“Tin Man”
The Enterprise races the Romulans to contact a space going lifeform.
"Devil's Due"
A powerful mythic figure returns to enslave a planet in accordance with a contract.
"The Wounded"
A rogue starship Captain threatens to destabilize the Romulan Neutral Zone.
Maybe someone else has others?

So here's a little rundown of the ones I think could have worked.
“Encounter At Farpoint”
The Enterprise crew is put on trial for the crimes of humanity.
"Code Of Honor"
Uhura is abducted and Kirk must defer to an arrogant leader to negotiate her release.
"Angel One"
The Enterprise seeks survivors from a wrecked ship on a world ruled by women.
"The Arsenal Of Freedom"
While answering a distress beacon the Enterprise crew is beset by a world of ancient weapons.
"Symbiosis"
Kirk is caught between two disagreeing factions while trying to adhere to the Prime Directive.
“Conspiracy”
Kirk suspects starship and Starfleet personnel are being taken over by some unknown influence.
“The Child”
Uhura is impregnated by an alien entity.
“Where Silence Has Lease”
The Enterprise is trapped in an unknown void and the crew subjected to tests.
“Loud As A Whisper”
A deaf and mute mediator is assigned to arbitrate bewteen warring factions.
“Up The Long Ladder”
The Enterprise answers distress beacons from long lost colonists.
“The Survivors”
Two people are the lone survivors on a world devestated by an alien attack.
“Who Watches The Watchers”
Kirk seeks to minimize Federation contamination of a primitive culture.
“Booby Trap”
While investigating a derelict ship the Enterprise also becomes trapped.
“The Enemy”
Sulu’s survival depends upon working cooperatively with a Romulan officer.
“The Defector”
A Romulan officer seeks to defect with vital information.
“Tin Man”
The Enterprise races the Romulans to contact a space going lifeform.
"Devil's Due"
A powerful mythic figure returns to enslave a planet in accordance with a contract.
"The Wounded"
A rogue starship Captain threatens to destabilize the Romulan Neutral Zone.
Maybe someone else has others?