This is a huge change, and one of the most discussed one for the Civ series. Previously, with stacking, you would get something called the Stacks of Death. 50 tanks, moving together, enjoy your defeat screen. It was silly, it made choke points irrelevant, and it encouraged massing units. More precisely, you were usually better off picking a unit or three, and building lots of those. This unfortunately meant that there were hundreds of units on the map, and all had to be assigned orders, making turns become half-hour long headaches.
There were also issues like city defenders- imagine a stack of 5 spearmen guarding a city on a hill. They are fortified, so that's a +25% combat bonus. Wall, +50%. There's a hill, +25%. We've doubled the combat value of our units, and there are lots of other improvements like Wall that give combat bonuses. This is probably one reason you got silliness like spearmen beating tank regiments. (To be sure tanks in Civ4 get combat bonuses against low tech units like spearmen, and ignore the wall, but you get the idea)
Of course, there were counters, like artillery units. It wasn't really something you could exploit for gameplay advantage, it just made large wars tedious. Still, when one of your main strategies for combat involves "suicide catapults", it just feels weird. Obviously this much-abstracted game series is not about literal realism in mechanics, but Civ has always aspired to maintain at least some semblance of verisimilitude. I mean, come on. Suicide catapults? Uh, what?
|First result for a "suicide catapult" image search. BTW, freakingnews.com, FUCK your watermark. And that's a ballista, not a catapult!|
You couldn't just not do it either. The AI always did anyway and if you didn't play its game, you'd be steamrolled pretty easily after a point.
Without stacking, we automatically get a bunch of wonderful shifts in the Civ playing experience. It makes far more sense to have less units, so micromanaging them is much less of a headache. Together with units like archers, which attack from a tile away, you end up fighting with formations: Defensive units in a line guarding the ranged units, which bombard the enemy, while cavalry on the flanks is ready to surround the enemy's column. Suddenly choke points are viable: Find the right 1 tile gap in a mountain range and you can hold of overwhelming numbers with a small group of units.
Granted, there are also downsides. One is pathfinding issues. The AI has no idea how to deal with the 1UPT, and will not protect their ranged units, or support their melee units. You can simply place 3-5 units at some chokepoints and have AIs send army upon army (they can really have crazy production output at higher levels). Because it can't path properly for some reason, after everybody is done with their opening turns can literally take half an hour to finish. Yes, I mean just the part where you are waiting for the AI to move. Half an hour.
Granted, the patch improved the wait times somewhat, but I don't know. I still don't like needing less time than the AI to move my shit.
The other problem is also about pathfinding, but for civilian units. It's really a special case of the first one, but I don't understand why they wouldn't allow workers to stack. It would make automated worker forces much smoother, and it's not like stacking workers confers any advantage. At best there's the trick where 5 workers finish a mine in 1 turn, but you can just disable that (I don't think it's even possible in Civ5 if you removed 1UPT with a mod). I guess it's a bit riskier, since you can capture a stack of the workers, but honestly, who cares? When has capturing workers en-masse ever been a serious strategy? It's just one of those things where it's obvious that to do it the way they did is more effort, and it's off that they didn't notice the easier, better way. I'm just baffled as to why they went with this.