I'm presently working on a 3D model based on a design I drew up about twenty years. It's meant to be a pre TOS era cruiser, one of Starfleet's earliest ships. I've even wondered if this ship could be similar to the Republic
mentioned in "Courtmartial" as well the Valiant
mentioned in "A Taste Of Armageddon," having gone missing without a word fifty years ago in the vicinity of the Eminian star system.
We know the broad strokes of what happened: the Valiant
entered the Eniminan system and fell victim to the war existent between Emniar and its sister planet Vendikar. Both Anan 7 and Sar alledge the ship was destroyed because of the ongoing hostilities and that the entire crew was put to death in disintigration booths (or so we assume).
It could make for an interesting story if fleshed out. Would the Valiant's
Captain have surrendered easily or would he have put up resistance as Kirk does fifty years later? Was the ship destroyed in orbit as the Eminians tried to do with the Enterprise
or was the ship voluntarily abandoned/surrendered and then the Eminians destroyed it or perhaps even canabalized it? Is it possible not all of the Valiant's
crew were killed? Were the planets then broadcasting a warning signal to stay clear of the system (as the Enterprise
encountered) or was it not yet in place? Maybe the Emniians started the broadcast after the incident with Valiant
in order to avoid any repeats of a similar situation for they couldn't know for sure if the Valiant's
authority knew what happened to the ship or if they'd come calling to learn its fate. Could the ship's fate have been precipitated because there's no communication between Emniniar and Vendikar and as such the Vendikarans couldn't know if the ship in orbit over Eminiar was a native ship or alien? If the Eminians let the Valiant
leave they could have been afraid the Vendikarans would interpret it as a breach of treaty---which, of course, is what they claim when the Enterprise
arrives decades later.
In "A Taste Of Armageddon" we see a flash on the Eminian war map and Sar exclaims "Look" to Anan 7 who replies that it's just like it happened fifty years ago. We can assume the ship wasn't actually destroyed at that moment based on how subsequent events play out when they try to take Kirk and the Enterprise.
In trying to presurre Kirk to surrender easily Anan 7 says the Valiant's
crew experienced the exact same fate. Well maybe basically, but it mightn't have gone down as pat as Anan alledges. After the flash on the screen (if it really did happen the same fifty years earlier) we really don't know how things transpired.
Of course, ultimately it's a downbeat ending because we know the Valiant
and its crew never leave the Eminian star system.