first of all, the new addition of a need for fuel is nice and now made the mod even better.
but at the same time, i barely could use my old map after updating because i had used this mod right from the start of the map as a replacement for belts and tried to somehow separate the factory into separate tasks (mining droids, columns of smelters, one column each for each science, all connected only by the transport drones), and i only just had gotten the basic oil recipe and temporary refineries usable for getting a little petrol for lots of requesters which each suddenly asked for 500 petrol ...

is it intended that the transport drones are only used starting at midgame, after getting to oil production and blue science ?
i have no good "quick idea" how to combine this meaningful and interesting requirement with being able to use the drones also in early game right from the start. maybe some tiers of drones, using lots of coal first instead of only a little petrol later? but how to supply the requesters with different fuels? maybe some kind of "burner requester" at first which request coal (or other fuel like wood or possibly later also solid fuel) for fuel and drones use lots of this fuel, and later (after some more blue research) the MK1 requesters (and MK1 drones?) can be quickreplaced with MK2 requesters and drones that use petrol (recipes could make the MK2 directly, or there could be recipes to upgrade MK1 to MK2). having MK1 and MK2 at the same time would have the advantage (also in the later game) of being able to use coal for small separate road networks with no need to build tanks, fluid suppliers and requesters, additional fuel depots, etc for tiny networks and having to move petrol for them back and forth across the entire factory.

currently, or also in the future (if you don't want to reduce fuel requirements in some upcoming version), should the research for drones and the first bonuses require only red and green science (like it is now) while the fuel itself requires having started using oil and thus blue science might be useful to immediately show that it is not intended for early game ? else, we would be able to even research some bonus techs before we are able to make fuel (petrol) ...

What about adding a recipe for, let's say, coal slush, made from coal and water? Or are the drones limited to one type of fuel?
You'd still need a blue assembler for my idea, so not strictly early game, but neither is green science (depending on mods).

Right now I use AAI vehicles in a very similar manner than your mod, and as that just reuses normal vehicles, you only have to worry about stocking them with "normal" fuel - but you don't get automatic logistics as with your mod.

@OhChirpy: the drones of this mod are completely different from normal vehicles.

requester depots are set to single item types and have one slot for drones (dedicated to that depot only) and one slot for petrol, and then automatically send the drones to fetch items/liquids from item provider depots and liquid provider depots, automatically and only internally fueling them from that fuel slot and also unfueling them after return. they now even can get ore directly from mining depots (from the "mining drones" mod) which can be used "stand alone" but also act as providers for this mod. a fuel depot is filled (via pipes) with petrol and also has a slot for drones which then deliver the fuel (petrol) to the requester depots.

overall, this is more similar to bots where you can't access them or their inv, but in contrast to bots they drive on roads (road tiles, made from coal and stone) and carry 1-6 (depending on bonus) full stacks of that item, and their number and bonus also determines how much of that item type will be available as max in that depot (instead of specifying several item types and exact amounts in a requester chest).

it's a new concept for transport and deliveries, an alternative to belts, bots, trains and vehicles. and it has its own challenges of setting up networks and balancing the number of drones (maybe even having low bonuses only, to not always require up to 6 full stacks of wires etc :-), and the required amount of items/fluids ...

I agree that an alternate early game fuel source would be awesome. I'd like to use mining drones + transport drones to get ore to the base just for something different than what I often end up having to do, which is run thousands of belts before I want to bother building out a train network since I typically don't bother there till I have all the stuff researched for logistic train networks.

Side note, a game not using trains at all, but instead using transport drones sounds interesting. 6 stacks + enough drones running the route would certainly provide similar throughput as trains, and look way cooler I think.

@alnet : yes, and there are additional challenges when doing it for long distances: you need to transport fuel in the opposite direction, use relay stations for items in one direction and fuel (including fuel depots) in the other direction, etc. another challenge is that the drones might have to travel a lot unless you split up the road network, but then you need relay stations again ... and of course, the cuteness factor always is much bigger than with belts, bots and trains, especially if you also use construction drones, and mining drones together with the "I, Robot" mod :-) LOL

I started a new using construction drones, mining drones, and transport drones, along with Factorissimo so that belts only exist inside the factorissimo buildings, while outside is all roads.

This new change has broken all that. Now I can't use roads untill later, once oil is set up. And now there's only a small window where my "city" is using roads to a "future city" with drones.

I don't think its that much later in the progression.

Before it was green science, and you needed engine units,
Now its still green science, but you also need basic oil processing, which is also green science,
And then just a small refinery setup, like 1 pumpjack, 1 oil refinery, and you have fuel for the system.

I also don't see how its a small window between green science road network, and high-tech science logistic bots, which are 3 science packs away.

Fair points, my complaints about not building trains until I have LTN stuff researched is also my own fault for relying on that mod, but I'll certainly have at least basic oil researched long before then. I think I may start a new play through relying only on transport drones, instead of trains. I'm betting that will look damn cool to just run around in, assuming the drones can't run me over like a train. :)