It's like in Clone Wars, I don't think they ever called them 'Venators', it was always 'Jedi' and/or 'Republic' cruiser. Jedi Cruiser was the internal name of it during the production of ROTS IIRC. I think Bad Batch might be the first non-book/comic/game to use the name Venator.
Star Wars has always gone with a "whatever sounds cool" approach when it comes to military nomenclature, whether it's ranks or vehicle classification, so I wouldn't sweat the "is it a destroyer or a cruiser" discussion too much as there's not a lot of point to it. I mean the Kom'rk is supposedly a "fighter/transport" while the LAAT is a "gunship"? That makes no sense. Even the term "cruiser" itself is of dubious value in a space vessel given that in the real world it was invented in relatively modern times to fill the gap between destroyers (which aren't usually very big) and battleships . . . then when they started making battleships that could keep pace with cruisers they had to coin the term "battlecruiser". And that was back when speed actually mattered in a naval engagement. Hell, even the term "destroyer" is a relatively recent one and tied to the invention of the torpedo, allowing smaller ships to be a threat to much bigger ships for the first time. So it's all fairly arbitrary and of the time. All that said, if/when they ever get around to the Old Republic, I think it would be fun if they took some old antiquated classifications and just stuck "star" in front of them (Starcaravel? Starghurab? Starship of the Line? Stargalleon? Star-Trireme?) instead of the more familiar terms, just to make it all feel ancient, because again; it's what feels right that really matters. As for how fast they could have built Star Destroyers; pretty damn fast. I'd say a year per hull, tops, if not half that. Just look at the sheer scale of the facilities over Kuat, Ringo Cinda, Corellia, and the like. Then look at how quickly they rolled out huge numbers of Venators in the first place, and a generation later, how fast the New Republic were able to field the first Starhawks *in secret*! Hell, if they can built something of the scale of a Death Star in anything under a millennium, then a Star Destroyer is a trivial endeavour!
It probably wouldn't be surprising if we found out Omega was at the Battle of Endor. Though I don't know if she would be an Alliance fighter pilot, or just a transport pilot. They need people to run missions and move equipment and personal around as badly as they need starfighter pilots.
In her teens, Omega had the tactical skills to escape from and cripple a major Imperial installation almost single-handedly. As an adult, I would expect her to be one of the Rebellion's strategists or intelligence operatives.
You can't have the entire Rebellion be present for the Battle of Endor, though. There just weren't that many ships there, even if the amount of time the fleet survived to allow the shields to be disabled before the Death Star had destroyed all of them might suggest they were slightly underrepresented on screen. However, going visually - she was most certainly present for the Battle of Exegol. But also not a good point to have her at, it's doubtful any shows will revisit the Battle of Endor, so it doesn't help us for a live action appearance; it's small-universe syndrome that doesn't even lead to a cameo, let alone a full appearance. But she may have been to the base on Dantooine, which can still have a live action appearance.
Okay, so there's a planet called Tatooine and a planet called Dantooine. Is there a planet in the middle called Inbetooine?
Not that I know of, but there is a Klatooine... https://starwars.fandom.com/wiki/Klatooinian ..and aVentooine. https://starwars.fandom.com/wiki/Ventooine
No doubt sharing a system with Baradooine and Niktooine. Though you should avoid Niktooine, it can cause cancer.
The rule of cool always wins out. "Star Destroyer" is just a great and scary name to go with. I assume the Republic has a committee that is all about coming up with cool nick names and designing Star Trooper and Empire style uniforms that really appeal aesthetically to the eye.
If we see the Batch in live action, do you think they would be Temuera Morrison or other actors? They technically are Jango clones, but thanks to their mutations they look pretty different from him, each other, and other clones.
They look and sound like variations on Jango. Hunter's a tattooed Jango with Rambo hair, Wrecker's a big burly Jango with a damaged eye, Crosshair's a gaunt Jango with a different face tattoo, etc. Which is why they work best in animation. I suppose they could be done in live action by digitally altering Morrison analogously to "Skinny Steve" in Captain America. But I'm fine with them staying in animation, or appearing in comics or prose. Not every character has to show up in live action.
I didn't think of doing a "skinny Steve" kind of thing with Morrison for the Batch, something like that would probably work.
I did know that. I was thinking of it with this when it started. The Old Republic plays with the idea a little.