While T2 or faction rigged structures can provide for great income, that income will hardly be made with T1 frigates. A Sotiyo in null has the same 1% mineral saving as its highsec counterpart has, while a T2 Small Ship Manufacturing Efficiency Rig provides for 2.4% ME in high, but 5% in null.
When it comes down to taxes, those are based on the industrial index, which is below 2% for most “backwater highsecs” and also is below 2% for most backwater nulls, while the industrial hubs, which are where the T2 large citadels are, have indices higher then that. Especially when it comes to reactions, indices will quickly show where the “reaction alts” are homed, as those systems spike in fees, making use of nullsec flashy T2 infrastructure costlier then the use of cheap unrigged backwater raitarus/athanors (including lowsec reactors and highsec engineering stations).
Let’s for simplicity assume you save 10% of the total production cost for heron frigates, which are the most expensive T1 frigates, and you fill a jump freighter with them, you get 150 Herons each selling for 0.7M isk, or 105M isk in total cargo, out of which you save 10% from using a hypothetical backwater t2 sotiyo at 0% index space over poorer highsec public accessible infrastructure, then you’d save 10.5M isk. That is hardly “great margins”, as you need to do that a thousand times to return of invest the jump freighter, the fuel price has not yet been accounted, and every time a venture cyno alt is blown up, it has to be replaced for around 8M isk… plus the inconvenience of JF-ing, jump fatigue, …
Great Income can be made with T2 or faction rigs on blingy infrastructure, but it’s not based on the per item price: The time consumption optimization that is provided by the rigs is almost 50% in null while it’s only 24% in highsec, which means that the null station pumps 35% more production in the same time as it’s highsec counterpart, so whenever yield is made, you make 35% more, independend of the production prize… actually you’re paying 35% more in null then in highsec within the same time, but you also end up with 35% output. If that output is output that actually generates yield, you end up with 35% more of it. Last time I checked a Survey Scanner II would provide 300% return of investment including average research cost, so I don’t care about 10% tax or not, and I can put 75.000 of them, or dozens of billions of isk, into a single JF… while the good old Damage Control II has considerably lower margins, but can be cashed out faster and more reliably as it has huge trade volume, and a JF can equally jump billions of isk worth of it in a single sortie. How much time does it take to create 75k damage controls? Certainly enough to make me consider using the 36% faster nullsec structure and jump freighting. T2 ammo/crystals of any variant goes like the DC2, it’s junk-priced per item but if you fill the JF it’ll be billions, and the trade volume for ammo is gigantic…
… less so for mining crystals but those are “expensive” per item compared to let’s say fury missiles. Oh, B-Type mining lasers, even the T1 ones, where quite nice yield last time I checked, too.
Accounting for JF fuel, production in highsec will be cheaper then production in null + JF-ing, but if the per-item yield is high enough and you can put enough items into a JF, the time saving will make up for it.
Likewise, farm Kernite in WH-Space where there’s huge rocks of it, and if you can’t compress it, drop it uncompressed at the storyline agent stations rather then trying to reproc it… you can easily sell it for a convenience premium and missioners will buy it.