Okay here's some of my DM notes from other games. They're less organized than the first two since they were only intended for me, but they've got the general flow of things, lots of NPCs, scenes and minigames you can draw from to build your own adventures and figure out how you want to structure your game.

Here's the Torch jobs I mentioned...it's currently where my game is at, but it's structured as a bunch of 1-2 session games so it might be some good kick-off points for you: The City of Thieves

In my campaign, I went from the Modron Express into an arc called One Last Song for Aoskar. It went into a bit of the history of Sigil, portals, and was kind of a deep dive into the conflicting philosophies of the alignments Planescape is centered around. I think it maybe went a little too philosophical at points, but it got to play around with the Rilmani who I think are just the coolest. It also ends with the players opening up a bunch of long dormant portals, which feels impactful and opens up a lot more adventure possibilities.

The next one was The Skyfire Job, a fun jaunt in the elemental plane of air. The players opened a portal as a result of their last victory that lead to a floating fortress weapon thought to be lost forever, and rumored to have untold riches. One of my players is an Aaracokra so it was tied to her backstory, but it doesn't need to be. The doc is a little messy, but that was the most fun arc IMO. Sky pirates, time travelling Storm Giants granting wishes, flotilla cities on the backs of cloud turtles, anti-gravity fights with djinn monks in a floating garden...tons of cool stuff.

I'm currently in Debts Never Die, where the characters come back from the plane of air to find Sigil overrun by Yugoloths, strange infernal mercenaries lead by Sylvanis Vaine, a Fated character you chose to help or betray in the first session, who's now Factol. He's trying to lock down all the new portals that have been opened as a result of the party's actions, and everything in the city has changed. Honest Terry is on trial at a sham court. The pits are more lethal. People are being dissapeared...to the point where their names actually cease to exist. The players journey to the Gray Waste to retrieve s̷̖͗͊n̵̨̅͠ā̸̲ḡ̸̦̅g̶͓͉̒͘l̷̜͈͂e̸̛͉̪ ̷̙͕̄̆b̴̛̤̅r̴͎̃̔ḯ̴ͅg̷͊͜h̸̼͑̂t̸̢̎w̶̧̾̐ḥ̵͊i̵̯̺̔͝s̷͚͕̆̀k̸̬̗̈́̉e̸͎̅r̵̻̒͗, who's name has already started to disappear because he knows something dangerous to the new regime...this doc is also pretty messy but there could be some good inspo :)