So my issue with Tales and G3 taking place at the same time is that in Tales you basically only have earth ponies. The only episode with anything else is that Up Up and Away one you mention. So do they just not know that other ponies exist? Why? Patch as you know, thinks the other ponies are aliens. So I'm not sure they knew other tribes exist at all in Tales. Is this something like G5? The tribes were separate but didn't even know about each other?
Well, that's where I think G3's bit of lore can actually come into play. In that series, we DO learn that all of these different tribes were separated and forgot about each other...for vague, un-elaborated upon reasons. Maybe some sort of disaster, or maybe not, they really don't go into it. The Earth Ponies, Pegasi, Breezies, and Unicorns all didn't know about each other until they just started re-discovering each other and befriending each other again. It's a TINY bit of lore in a rather lore-starved generation, and it's always stuck out to me as something I wished they'd play with during a crossover or anniversary celebration or something.
So, in this context, the G1 ponies (or their ancestors) would be "guarding the wall" so to speak. Being the front line of all the horror-terrors of their land and protecting everyone else. Even if they had LONG forgotten that was what they were originally doing. Guarding their borders from all the other monsters and sorceresses that want to invade and kidnap their people.
And the Tales cast could be a FAR more advanced civilization that keeps to itself. Think like Atlantis or Wakanda. Only their "far future" tech is still stuck in the 80s, so their walkmans TOTALLY blow the other ponies minds. Honestly, the characters in Tales never did seem to leave their town. So ONLY their town being as "advanced" as they were COULD be a acceptable retcon...maybe. I'll admit, it's been a while since I've seen Tales. They probably do mention other towns or cities.
The more I think about this, the more I like it. I know it's stupid. And I'm not sure if I'd actually want Hasbro to go this way. But, I think there's story potential here. You tie up a long standing "loose end" from G3. You give a nod to the comics. You get a chance to have characters from all these generations interact with minimal headaches. And you have a chance at giving us a little bit MORE lore, because you'd explain what villain or cataclysm CAUSED the different pony tribes to separate in the first place. Overall, I think it could work. I actually wouldn't mind if they went this way.
Honestly? I like your guy's timeline's too. They work. And they tell a story.
BUT, I do think it's unlikely that Hasbro would be okay having the different Generations out of order. I think that Hasbro would think that KIDS would think that having G3 take place BEFORE G1 would be too confusing. Or having Tales take place between G4 and G5. I do think they'd try and FORCE them to be in "order" somehow. G1 to Tales to G3 to G4 to G5. So, how would THAT work?
To be honest, it almost works. G1 to Tales works, because you have a reasonable progress of technology and society at play. From "medieval" times to "80s suburbia". It kind of works. And similarly, G3 to G4 works, because you have a bunch of different societies beginning to comingle and discover each other and become one big government.
The big problem, I think, comes from going from Tales to G3. If that happened in THAT order....we're missing a BIG piece of the puzzle. But honestly? Even THAT kind of works now that we've gone from G4 to G5. It's possible that at certain points pony society just...self-destructs. That'd be a REALLY dark take but....given where we are in the real world, you actually might be able to make even that work. Maybe kids need to learn that, yeah, sometimes societies just rip each other apart. It's not a lesson enough media teaches, if you ask me!
Maybe you could turn it into a villain making history repeat itself and destroying pony society on purpose? EVERYONE teaming up to stop them from making the cycle repeat again?
There IS the question of why no one seems to remember the events of Tales or G3, since G4 and onward only really EVER reference G1. But...there weren't as many cool villains in Tales or G3. It's kind of like most kids knowing the stories about King Arthur or Robin Hood. Those are cool "historical" stories. But, no one really tells stories about...John Stevens the father of the American Railroad system or DELAG the German company that founded the first commercial airship. That's "boring" history book stuff. (Mind you, Twilight WOULD almost definitley had been into ALL of that, but at least we can sorta wave it away.) And all records from around "THE DISASTER" would have been destroyed, so no one really has any idea what actually happened, to help the plot happen. Maybe everyone kept everything on their phones, and when those services went down EVERYTHING went with it.
