There is no 'obvious how much is too much,' except for individual players. IMO, devs and critics are better off if we all focus on an assumption that underlying complexity is good but that how and when players must directly engage with that complexity is a matter of taste.
Of course. But before we ask for anything we have to be sure of what we want. Its pretty obvious that pidgeon doesn't like the idea, which is good. If he doesn't then its quite likely that I won't either, im just not sure yet.
I thought the discussion was about Seperate Mounted Combat attacks, covering both Mounted and Unmounted, and what happens to the Mounts if their Riders are lost.
The original topic was based around a yes or no question. I voted for yes, but that answer by itself is not useful for anything or anyone. If I had left off at that this conversation certainly wouldn't have gotten even this far. To get anything useful out of a conversation or idea you have to follow up on all possible leads.
The rider is not neccesarily the leader. If you are riding an elephant and the elephant gets angry or spooked you are no longer in control. It would be akin to gost riding a semi trailer. It depends entirely upon what method of control you are using. If the rider is the one who directs his mount then the loss of a rider means a loss of direction. If the animal is trained to respond to commands that never come, it will either get confused or do nothing.
War bears from master of magic are summoned by wizards in pairs. The leader in that case would be you, these creatures are magically linked to you and presumable obey your commands. If you did something similar in Elemental only this time you place riders upon them, it wouldn't matter if the rider dies, the mount will still obey your commands.
When I said "animal infantry" I was just categorizing those war bears based on what they are. If these were wild bears then they would have no leader to speak of. If they were trained war mounts its possible they could respond to outside commands such as horn calls. If they were magically summoned then they would obey the commands of the summoner.
Leaderless bears are still very dangerous. In an offensive capacity the lack of control would cripple most tactics. But imagine if you loaded them into hidden cage traps, put them to sleep magically and waited for an invader to attack your city. Every street corner they turn would essentially result in constant OMGWTF BEAR AMBUSH!
Gives a new meaning to the name "bear trap". 
Unless of course, you are avocating that we be allowed to simply build Bad Ass Bears Brigades, in large formations.
That would be like having pie with cake IN IT. 
It would drive me absolutely insane to have to constantly make sure that all my armies are going to have enough food, equipment and whatever else they might need shipped to or following them every day. I'd rather they just implement logistics ala GC's life-support (although I wouldn't be very happy with that either).
Hmm. Well in most games your starships have some sort of "fuel" rating. You can extend the range of ships by using tankers to refuel them halfway. I suppose the supply system in Elemental would work a bit like that.
It doesn't have to be user complex. I'll just make up an example here. Lets say you dispatch a supply convoy from your home to your army every day. This caravan contains 100 supply points. Your army would have different supply meters that represent different things, food would be a major one, equipment another and other stuff such as mounts or siege weapon ammo. Lets say your army had 50/100 food points, when the caravan arrives it only takes 10 supply points to refill the food stocks. The other 90 are spend restocking other things, depending on how expensive the item is the more supply it is worth. 1 point = 5 food or 4 bundles of arrows, 2 points = 1 sword, 5 points = 1 mount etc.
If your caravans arrive daily then your army will never lack for anything. If there are supply issues and caravans only get sent out once a week the army will still have enough to eat but thier stocks of other items will begin to degrade. This kind of detail would allow lots of stuff. Say you were attacking a city and the city had plenty of food but was low on arrows, if you intercept the next 3 caravans they would have no arrows left by the time you make your main attack.
From what we know of the unit building system, this kind of supply system would not be far off.
Personally I would find this maddening. I like the "zone of control" idea, where maintaining an occupied fortification gives you a zone of control that hampers enemy movement, though. And if you're so into realism, then what's to prevent your army from pillaging the surrounding enemy territory for food and supplies?
Yeah exactly. Forts can be used in an offensive capacity as well as a defensive one. Your raiders could do out and cause havoc then retire to a safe stronghold. Having a fort or at least a stationary camp allows you to bunk more soldiers and frees up sentries to go scouting.
My point is that there are many ways of achieving these goals without all of the tedious management your suggestions would require from the player. At least in my opinion
With the caravans at least its really not that hard. When you are creating your empire your territory will be divided into zones, even if those zones are not separated by lines on a map. For the "dead zones" between cities its a simple matter to plop down a few waypoints and forts. Placing these in good locations is a necessary skill, you don't want your caravans trudging through swamps. Once these points are down the computer would connect the dots automatically and route caravans through the quickest and safest route. You wouldn't have to directly control them unless you wanted to do something special or there is a threat affecting them.
If your army is in enemy territory then you would need to put in some more effort. But at this point it would be another layer of tactics. Do you escort your caravans with enough troops to make them bulletproof or do you bring them in by stealth?
Okay maybe I could have phrased that better, I was in a hurry. Mounts are powerful because they can support riders. 1+1=2 But if mounts die when the rider dies then that equation becomes 2-1=0 which doesn't make sense at all.
You can remove the entire unit from the battle if it loses one of its parts, but the loose half doesn't have to evaporate. Even if you only keep track of the surviving half in a logistics capacity, that would be a huge improvement because surviving resources can be used again.