and if there is an Earth map it certainly will have some wide open spaces.
Will there still be wide open spaces? Sure. But if you're a small civ confronting a large one, that's not where you choose to fight.
You also get artificial choke points added from civ borders; even on a flat open plain, you don't get to enter tiles of civs that you aren't at war with who don't grant you open borders. France/Germany have a chokepoint border if Germany isn't willing to declare war on the Low Countries.
You also get some choke factors from river crossing, since you really don't want to be trynig to attack across a river.
And an earth map will have plenty of choke points. Pyrenees, Alps, Italy is pretty narrow, Istanbul, Gaza, India vs China, India vs Burma (compressed below the himalayas), pakistan vs persia (narrow mountain passes), central America, the rockies, the andes, just to name a few.
IMHO 1 unit will make it worse and small countries with limited units will have less ability to win a war than before.
This just doesn't make sense to me; the only way in which it could possibly be worse is because you can't hide in a city anymore. But a big enemy army in Civ4 can knock down a city's defenses in a turn or 2, and then wipe out your smaller army with their larger stack.
In Civ4, it is easy for a larger army to concentrate their entire force simultaneously against a weaker force. In Civ5, this isn't the case.
In one basic manner I have to disagree with you that large stacks of men and equipment smashing against each other is not how reals wars are fought. That may not be how modern wars are fought, but that was very much how wars were fought in much of history.
The "smashing armies against each other" critique is complaining about all the player has to do is move their stack into the enemy stack.
Yes, until the 20th century, wars were about manuever of armies and major battles where one army confronted the other. All of these historic battles *were* armies facing off against each other, but still had plenty of scope for feints, flanking, pincers, focused line breechs, and kinds of other tactical manuevers that Civ has never given us the chance to pratice.
Many players (including myself) get really bored by the purely strategic combat level of Civ3 and Civ4 stacks. We like 1upt because it offers some tactical opportunities (eg being able to use which unit my unit attacks, rather than just facing whatever specialized defender does best against my attacker) that we haven't had with big stack combat.
Not until the 20th century do we evolve (or devolve) into the concept of total war where defeating an entire country or peoples is the norm. And what else is a defining aspect of many of those battles? they are focused on cities!
Most 20th century battles are *not* focused on cities - they're often named after a town nearby (think: Kursk), but mostly they are out in the field. For every Stalingrad there are 10 others that are not based in cities.
WW1 and WW2 warfare is much more about fronts; 1upt does a much better job of representing armies opposing each other along long frontiers.