For the old cata era 1-60 experiences, the pathways went like this. I’ll base them off the racial paths. So humans would go this way, orcs that way etc. It is important to note that zones like Azuremyst / Bloodmyst isles along with Eversong Woods and Ghostlands are in the TBC timeline. So chronologically, you would go to Outland following those zones. Likewise the DK starting experience for core races (minus Pandaren) is early Wrath. So Wrath zones are the next one afterwards. Demon Hunters of course should go straight to Legion following their starting experience. In which the first half does take place in TBC. Anyway, here are the pathways for each core race relative to their time period.
Alliance:
Human: Elwynn forest → Westfall → Redridge Mountains → Duskwood → Northern Stranglethorn → Cape of Stranglethorn → Western Plaguelands → Eastern Plaguelands → Badlands → Searing Gorge → Burning Steppes → Swamp of Sorrows → Blasted Lands
Alternatively, after Cape, you can go to Dustwallow Marsh instead and follow the path in the night elf / worgen section afterwards.
Dwarf & Gnome: Dun Morogh → Loch Modan → Wetlands → Arathi Highlands → Hinterlands → Western Plaguelands → Same as human from this point
Night Elf / Worgen: Teldrassil / Gilneas-> Darkshore → Ashenvale → Stonetalon Mountains.
From here you get the first of two splits
You can either go
Stonetalon → Desolace → Feralas → Thousand Needles or Stonetalon → Southern Barrens → Dustwallow Marsh → Thousand Needles. Both routes converge with Thousand Needles.
Thousand Needles → Taranis. From Taranis you got another split.
Taranis → Un’goro → Silithus or Taranis → Felwood → Winterspring.
Draenei: Azuremyst Isle → Bloodmyst Isle → Outland path
Horde:
Orc & Troll / Goblin: Durotar / Kezan & Lost Isles. From here we got a split choice. You can either go
Durotar / Kezan & Lost Isles → Azshara or Durotar / Kezan & Lost Isles → Northern Barrens. Both paths lead to Ashenvale. From there follow the Night elf / worgen path. I will say that Goblins should go to Azshara as it does follow up on some of their starting experience plot lines instead of Northern Barrens.
Tauren: Mulgore → see orc & troll / Goblin line.
Also you can get a breadcrumb to go to Northern Stranglethorn at some point if you choose to go there instead. I believe you got it after Ashenvale. If you go down this path, follow the main human line.
Forsaken: Trisfal Glades → Silverpine Forest → Hillsbrad Foothills → Arathi Highlands → Follow Dwarf / gnome line
Blood Elves: Eversong Woods → Ghostlands → Outland Path.
Neutral:
Pandaren: Wandering Isle → Pandaria
Dracthyr: Forbidden Reach → Dragon Isles
If you are going for a true chronological order, then you should start with TBC zones, then Wrath and then Cata era etc . That includes the old 1-60 experience then the old 80-85 experience.
However it is implied that zones that shared the same level bracket happen around the same time.
As for dungeons and raids. They are a mess. The vanilla era has seen a few dungeons and some former raids updated for Cata’s timeline. These include
Stormwind Stockades
Deadmines
Shadowfang Keep
Stratholme (more like a model swap for some bosses and trash mobs)
Zul’Gurub (end game cata)
Zul’Aman also got a Cata update. So the Burning Crusade version is gone. Like Zul’gurub, this is set in the end game part of Cata’s story. So post Twilight Highlands.
Others got updates in MoP and WoD respectively. Now whether or not these dungeon updates match the timeline of those expansions respectively, I do not know. I believe they are set around Cata with one exception. That being Upper Blackrock Spire. The following vanilla dungeons got updates
MoP:
Scarlet Monastery
Scarlet Halls
Scholomance
Ragefire Chasm
WoD:
Razorfen Kraul
Razorfen Downs
Blackfathom Deeps
Upper Blackrock Spire
I believe WoD’s UBRS takes place before we begin our invasion of AU Draenor. You could do the first three bosses during WoD’s prepatch after all. Also doesn’t make sense to leave Zaela alive until after AU Nagrand’s story.
The rest of vanilla’s raids and dungeons take place during actual vanilla. Except Gnomeregan, at this point the dungeon is non-canon as Theraplugg dies in Gelbins stort story. So these include
Ulduman
Maradoun (did get a limited time cata prepatch version that saw the canonical end of Princess Theradus)
Wailing Caverns
Dire Maul (all 3 wings)
Lower Blackrock Spire
Molten Core
Blackrock Depths
Blackwing Lair
Ruins & Temple of Ahn’Qiraj
Temple of Atal’Hakkar
Zul’Farrak (did get a limited time cata prepatch version that doesn’t really mean much in terms of the lore)
Note that the vanilla versions of Scholomance and the Scarlet Mono wings are back in the game
Also Naxx and Onyxia’s lair got updated for Wrath. Although neither the vanilla, nor the wrath version of Onyxia’s lair is canon. Since she dies to Varian Wrynn during late TBC.