If you're just talking about generic item types, then it's definitely:
1) Initiative booster (wired reflexes, etc.)
2) Weapon of choice...
Your list and mine are fairly close, except for one element which I'll revise as essential only for the "Black Trenchcoat" style of SR, and not for the "Pink Mohawk" style of SR:
in *some* SR campaigns, a method of concealing or spoofing one's identity is essential. A party could legitimately refuse to include someone who was just showing their face, plain as day, and had a picture of that face on their ID, and who lived at the residential address shown on that ID.
Because shadowrunners sometimes make enemies, and being easily findable in a "Black Trenchcoat" SR game will lead to a hit team catching you with defenses down. And then interrogating you, and finding out everything you know about your teammates, before they flush what's left of you.
And that leads to another parallel to D&D and other TFRPGs: what happens between "Adventures".
If "You ride home in triumph from the Castle of the Necromancer, carrying piles of loot" is the end of a session, without spending so much as a *minute* on what the PCs do when they get home... well, that's a playstyle option, and it's certainly not how I roll. (Because shower first, or a Cold One first? That's what I've been thinking about, every mile of the journey from the Castle of the Necromancer to home sweet home. Except if there's a sweetie waiting at home, a kiss comes first, before Cold One AND before shower.)
If the next session starts with "Your next adventure is the Quest of the Dragon Gate, and along the way there's a pack of dire wolves, so place your figures on the battlemat"...
...well, darn, clearly your playstyle has zero interest in what the PCs did in the intervening month. That includes *not resolving whether they spent any of the treasure from the Castle of the Necromancer*, or at least not resolving that topic in categories B C or D. If Zapp demands a category-F-compatible method of spending gold on magic items, then that requires a category-F-compatible Thaum-Mart.
Come to think of it, there's plenty of episodic fiction along those lines, from some versions of Sherlock Holmes, to a variety of police dramas, starship dramas, etc. Then again, that's only *some* versions. The Cumberbatch version, for example, has an episode in which Holmes solves a murder mystery at a wedding... the villain is hauled away into police custody... and then the episode is NOT OVER YET; it spends just a bit of time on whether Holmes dances with anyone at the reception, and his deductions about Mrs. Watson. The reboot of Battlestar Galactica spent some episode time on things which happened while Vipers were on standby, rather than only spending episode time on things which happened from Viper launch to Viper re-docking.
So, here's how I intend to run the next phase of Tyranny of Dragons. The PCs have interfered with enough of the Cult's operations, that they are visibly a thorn in the Cult's side. The Cult isn't going to keep planning operations for the PCs to show up and foil. The Cult is gonna go after the PCs, find out who they are, where they live, and how they can be stopped *before* they foil another Cult operation. And then the Cult will sacrifice them all at an altar to Tiamat. Or possibly five altars, one for each head.
Well, that's the Cult's intent, anyways: get rid of those meddling kids. In practice, the PCs will have plenty of chances to notice and to take countermeasures. Those events will be played out while the PCs are meeting with faction contacts, with their Black Knights contacts, while training skills and practicing professions and generally *having a life between adventures*. Eventually one of those casual downtown RP incidentals will lead to an Initiative Roll and a showdown and blood. My goal is for the players to *not know until it happens*, whether "I sell my Wand of Magic Missile because I want enough gold to buy magic armor" is the trivial event which will lead to a fight scene, or whether it's "I go to the Temple of Kelemvor to multiclass as Cleric", or whether it's "I go to the Laughing Goblin inn and perform a song about my team's heroic defeat of the Necromancer".
Therefore, at my table, "I go downtown and find someone selling a +3 longsword and buy it", is not a category F event. It's a category D event, which might turn out to actually be category B or C.