No problem at all Vendetta187, I'm glad you took the initiative hehe.
My thing is, I don't see Pioneer's the issue whatsoever when it comes to city-spam. And I feel making any radical adjustment to the cost of Pioneer's would just overhaul the whole game negatively without any benefits to boot. I don't mind if there is a reasonable increase in the Production required to manufacture them, but to make it so expensive that there are so few, only ends up throwing off the balance of Research-oriented Improvements, Traits, etc.
Also, just giving them a higher price tag doesn't truly fix the issue being city-spam, because the strategy is to ALWAYS build many settlements, whether to simply cap resources, or future specialized centers. We mention what we know motivates us and the AI to pursue non-stop expansion, yet we are not tackling the underlining being the technology tree, the game mechanics area and such that influences factions to thus far simply expand, rather than "go tall" and focus on more manageable empires.
Research costs bloating for larger empires I'm iffy about, but it's an interesting idea to burden over-stretched nations with. We have many potential issues the more we try to "Fix" it.
Frogboy recently stated in the AI thread that monsters will no longer salt the land the first tile a City was settled upon, had he not been known of this, it would frustrate the strategy process of FE.
Our next issue is, we can instantly Raze cities as monsters do too. Factions and monsters should not be allowed to instantly burn an entire settlement down, but in a series of turns, to prevent outright loss in one instantaneous turn session, so we do not have to build an entire city over that took 50-to-100 turns.
I don't think we should try to revamp the reality that when one faction gets swiped by another, that Pioneer's should suddenly be easy to mass-produce to give them an advantage, especially so far in any game session. I don't think that's an issue to be honest, at all. Most importantly, what would we do with the placement of Outposts? Assigning Scout's to be Outpost-builders is another balance issue that shouldn't be discarded and brought upon another unit in my opinion.
We shouldn't add any restriction whatsoever to cities like the army system, foremost because they're both entirely different mechanics to compare and contrast, but the major aspect of the game is - city settling. I feel an entirely new mechanic at most is required to simply implement Civ-4's City Maintenance system that works exactly the same when it comes to increasing the amount of Gildar you're charged for every city you possess in terms of totality and distance from Capitol. The Unrest modifier should also play an important role in FE, that also operates similarly with the circumstances City Maintenance imparts too.
One perception/idea I agree the most with both you Vendetta187 and Drusus is the atmosphere of Wild Lands disappearing so rapidly. The idea of the game is that you are supposed to build a fledgling empire that conquers vast amounts of the world, brings back civilization and order to the chaotic charred lands, FE certainly needs more "Wilderness", more "danger" abroad. I'd strongly suggest FE having some sort of dynamic wilderness feature, that determines how civilized your game session is, and how advanced all the factions are, and begins randomly spawning new, harder, monsters around settlements based upon their type. Thus, 100-300 turns in any game, Cave Bears and their Den's will re-spawn near Outpost's, Hoarder Spider's and much harder mid-game bandits will spawn dens near your Town's and Conclave's, and much much more.
Player's shouldn't be punished in their city playstyle, it just needs balance when it comes to one faction gobbling so much territory versus another. We need some sort of mechanic, with series of Improvement's and effects added to current technologies that favor large and small empires. Technologies that reduce the cost to upkeep a softcap limit on cities, and technologies that give more bonuses to empires that maintain smaller, more potent settlements versus their larger variants. And when we begin to give the game some system that not only punishes them, but also rewards them incrementally on how many cities they have in a regulatory format, not in a restricted format, they'll take risks of expanding much more early on or later on. There is currently no reason to ever stop expanding with new cities and outposts so far, only 100% positives, no negatives to pro-and-con with.