This topic is still going - I am still against a fuel cost for structure placement, but having some sort of "net work connection fee" (for the lore) feels to be the best way to keep the number of structures balanced.
Reduce/remove a number of NPC stations in game - or make them so players can't interact with them - pushing players to use more player owned structures and services (if in HS/LS it creates a reason to go to war. war system needs an update as well) creating content drivers. Yet the system needs to be balanced in a way that prevents the powers that be from creating a massive donut again. Having an NPC tax on the structure owner means they need to decide if they can make it an investment that can pay for itself when the place it.
The system should try to get as close to real world business management as possible. Everything in RL has upkeep cost. Smart business leaders figure out the best way to use as little capital to possible to have the biggest return. Even empty buildings have upkeep in taxes and maintenance.
Corp A lives in a remote area for industrial reasons and find that having an Upwell structure for refining/industrial purposes is needed, plus they make would enough from taxes to pay for the monthly cost of fuel and NPC tax.
Corp B has capital to place a number of structures to meet what they see as the needs for the players in multiple places, and spread out their services across a region. Yet they don't have the ISK revenue to maintain all the structures fuel and fees, and thus their business module fails
Corp C, much like B has upfront capital to invest heavily, but pick target locations with more control and focus on creating a market hub, where players come to, so they can exchange goods for ISK/goods. They make the ISK to pay for the fuel and fees from their controlled market.
Tyranny and excessive fees are put into check due to the possible NPC markets in the region as well.
To me: the EVE economical system is all ■■■■■■ up now that we have tons of player structures popping up all over the place, with no real built in check and balance system. The system shouldn't just let people throw up more storefronts in an area already overwhelmed by storefronts.
How the fee system should work is up to CCP, but the easiest would be to just charge ISK.