The pet tournament got super annoying after a while and your comment about using the same strategy very much applies there as well
Kazaak and Ordos and the Celestial World Bosses are functionally the same
The pvp was a gimmick that just resulted in grinding
The buffs were too good and basically required to do any of the solo content, Tanaan has buffs too but they are more flexible and not required, which is better
The Tanaan factions at least provided some options for grinding or long term questing whereas the Isle faction was nothing but endless tedious grinding
The rare spawns in Tanaan are once per day which is infinitely superior. There's still rares on the Isle I've never killed because you have to camp them.
Apexis crystals were useful far longer than coins were
Tanaan has chest spawns and things you can find randomly forever while Timeless Isle chests are purely one time per character
Yes, Tanaan had shitty terrain and aesthetic, but the gameplay design is basically a direct improvement to everything from Timeless Isle. "Make your own fun" rare grinding for a tiny drop chance for toy or pet number 50 wasn't good design. Tanaan was much closer to the world quest setup we have now.
Timeless Isle was *maybe* better for people who wanted to literally be on the island farming and grinding all day every day. But for any sort of reasonable playstyle Tanaan is an improvement.
Note, I'm just comparing Timeless Isle and Tanaan design in a bubble, obviously WoD had a myriad of issues and Tanaan suffered in that context.
And besides, we know that Legion content is just going to be a further extension of the world quest system.
Timeless was miles better than Tanaan.
Timeless Isle and Tanaan both represented the single final outdoor activity for a nearly year long drought, you can't look at them 'in a bubble' and ignore that. timeless isle literally had shit to do that would take you the rest of the expansion at a casual rate, and it had people DOING that stuff the entire time because of it. It created its own little ecosystem and it was entertaining.
You say hte pvp was a chore. Why? It was pretty awesome 90% of the time. You absolutely did not 'need' any buff to do anything on timeless, they were just convenient. Similarly, the slower rare spawn rate directly led to a better community feeling there - a good rare would spawn and everyone would flock to it, you could actually count on seeing the regulars any time something cool was coming up. Along those lines, the rewards there actually felt cool and meaningful, instead of a bunch of random 100% drop shit that everyone had after the first day which then became worthless. You could get a cool pet drop like the Ruby Droplet and go "Oh nice!" and keep it and feel cool, or trade it, or sell it on the AH. You had awesome items like the fucking falling star that let you rocket around the world as a meteor. You had reasonable little minigames like the crane falling coin collection and the trivia daily game. The different areas of the zone served distinct purposes and had tiers of difficulty, instead of just a mishmash of 'here's the fel orc part' and 'here's where the beasts are' but they all feel exactly the same.
Tanaan might as well have been exhausted of content the first day for how meaningful any of it felt. It took all of the goodwill they earned with timeless isle and squandered it by losing the plot of what was actually fun about timeless isle. You're right, you couldn't finish Timeless in a week. Good thing we didn't have a week of the expansion left.
Also it seems ridiculous to bitch about the pet battle part, that shit was beyond optional, as far as pet battle content goes it was the best in the game at that point, and it's certainly not relevant to how cool the isle itself is.
Summation: The Timeless Isle is actually the single best piece of outdoor repeatable content they've ever made in wow. Still. I can't even imagine how many hours I spent there, and I STILL need a crab pet to drop before I'm done.