>repair
Mmm
How about an item/consumable which repairs a certain percentage of combat readiness fleet wide (say 15%) and hull/armour instantly (more than 15% I guess?), or it repairs one ship to 100%, including combat readiness to 100% even if it is above the ships combat readiness cap (it will degrade down to the cap anyway if the item does not interfere). "Repair nanites" or something? Probably not needed but might have certain niche uses, I'd limit it do half a dozen of finds per standard sector, might be useful if you pause right before a fight to restore your ships a bit.
Maybe a consumable that extends peak performance time for the whole fleet for a possible "boss tier" drawn out fight, or a consumable which does the opposite but buffs your ships, maybe with even more drastic consequences, possibly buffing vent speed, flux generation, damage, attack speed, I mean fire rate etc, as consequences ships that get disabled blow up or something, also faster CR decay or something.
Or an item which permanently alters or buffs (or exchanges "attributes" of) a ship as a non S-Mod inbuilt once applied.... Oh, wait. Anyway, how about some Domain tech builder drones which instantly get the colony running by building the first x things/industry instantly?
Tbh I find these ideas, my ideas from this post kinda meh since I am more interested in more weapon and ship options and planetary conditions...
Now more interesting imo: some kind of item which links 2 places like a gate, lets call it "Space Folder Coupling" or something, lets say I bind some of my outer colonies or rather one planet/place/station in in that system to my main planet and it lets me instantly travel between those places without running around searching for a gate, that would be &%$! nice QoL, probably an item only available once in a sector, easily colony item tier imo.
And lel you are free to use the ideas as you see fit/like/want.

I hereby grant permission to pappyodaniel to use this concept in their upcoming mod. kek

E:
- An item that increases burn level of the fleet for a few days
- An item that makes the fleet immune to damaging terrain for a few days
- An item that makes the fleet sensor signature smaller for a few days
consumable item that upon use instantly surveys all planets in system? That way in systems with alot of planets you can pop one to save time and know if any have ruins to explore.
...
Me like these.

E2: Yes, TASC
https://fractalsoftworks.com/forum/index.php?topic=17094.0 has the option to enable gate construction on stable points I guess, but the "Space folder coupling" thingy would link 2 places without running around to a gate across the star system...
How about a consumable which buffs the amount of goods a certain industry/resource on a planet yields for a while to increase/give a steady flow of credits instead of an instant return? Or an item (consumable) which teleports a selected ship or groups of ships back to my storage so I don't have to go back to dump my mothballed, salvaged ships and can keep exploring?
E3: How about consumables which give logistics/troop non space combat advantages, like drones as light and heavy ones found in bulk of hundreds or thousands but take no crew/goods slots and replace/supplement marines and/or heavy armaments? A few stashes or (military) bases hidden in the sector or on planets, or maybe on a salvageable military capital/dropship, being illegal goods and all, would enable a fleet without decent crew/goods capacities to raid or just give an advantage by bolstering numbers, you would still deplete them with attacks so it is a consumable.
E4: How about a consumable item or even ship! which acts as a failsafe to prevent loss of ships after a fight? Very rare and one use only... Gets consumed after the fight I guess? Or at least if (lost) ships were restored.
Maybe a consumable "biomass converter" or something which lets your fleet (supplies and fuel) run on food/organics for a while?
E5: An item/consumable which lets me drag a planet for a short distance into another free orbit to make a hot planet colder or vice versa to improve conditions would be really nice, now that one I like! [plantery engine intensifies] or some gravity magic shenanigans, maybe with a downside by permanently adding tectonic activity... Or making a hot planet hotter and slapping Cryoarithmetic Engine on it.

Me like. [grunting noises lel]
Stasis field (generator): Prevents all loss or gain of hull, armour and combat readiness outside of combat, limited charges/duration. Maybe it can affect supplies and part of the fuel consumption too...
Domain Gemini Matrix copy generator thingy something something: Consumes x of equivalent or greater value and grants y if you already have y so it makes a copy. Items? Goods? Ships? Colony items? Consumed upon use. Lets say it is limited to standard vanilla ships or some colony items, corrupted nanoforge vs. soil nanites or consume a Paragon to grant an Odyssey... This sounds good as an exchange mechanism, me like.
E6: Infiltrator drone as a consumable: Either gets a bunch of blueprints from the targeted planet, more with a HQ and orbital works with a nanforge maybe? Or sets to fleet points (Nex) to zero for that faction for a while to prevent attacks, or maybe it just siphons credits, based on the planet I guess? Or maybe it scrambles some industries? Or maybe it takes over one of the ships available on the market or from the faction? Or it disables patrols/fleets coming from this planet/station, makes them slow/they don't move or the CR is impaired/zero... So many options... Or the drone has data for juicy loot or some domain secrets. Or it can discover some other secret on a planet with ruins... Or maybe it buffs the next loot plundering operation... Or maybe it scrambles all stable point objects in the system or part of the factions and fleets run around like headless chickens, maybe some end up falling into the sun. o.O

E7: Yes, one can already introduce false readings, but the effect of the "infiltrator drone" could be stronger or faction wide. Emperor - Battle for Dune had infiltrator drones, they were cloaked, floating bombs which also had the ability to detect other invisible units as far as I remember. Good times.
https://en.wikipedia.org/wiki/Emperor:_Battle_for_Dune