Here's an example of bad unit placement.  The defenders unit at the bottom was so far away that it was out of the battle.  The unit got only one turn and the battle was over before they could take another one.

This has been quite annoying with the beta. I am not quite sure why the battle fields had to be reduced. This wasn't such a huge problem with the larger battlefields as you had a round or two to get your units into a combat formation. If the battle field must be shorter, maybe split the difference the new and old ones.

Other option is a group formation screen. I don't think anyone has mentioned this yet, but you could set how you want your units to spawn in general in some menu, so every map they spawn in that relative position. I think that would be the best solution (although could be technically tricky).

A tactical setup phase is the solution here. There is no need to reinvent the wheel Stardock. There is no need for clumsy pre made formations. Being able to setup your troops prior to combat is simple, logical and and practical. It represents a commander telling his troops where to line up and avoids the obvious AI placement flaws. The option for auto placement should be on each pre combat screen to speed things up if the fight is expected to be easy.

The armies overall initiative and level could have an effect on the size of the green zone in which you are allowed to place troops. Placing units in defensive mode would incur a first round initiative penalty to the unit. Ambushes could be implemented on the strategic map. During an ambush your units would be auto placed and incur a penalty to initiative. 

This is so obvious I find it hard to believe it isn't already in the game. This game is so close to being great I would really hate for tactical combat to be neglected without such a feature.

This is my favoured solution. In addition to the idea that stave-wielding mages should be placed at the back where they belong, I like the notion of the "Battle" button giving you a quick prompt where you can choose between formations like:

"Aggressive" - Melee units start pushed up in a staggered tactical formation wherein every unit can squeeze through a gap to engage on the enemy immediately. Ranged units in a loose formation at the rear. Good for when you want to be able to go all out from the get-go and screw the counterattacks.

"Defensive" - Melee units start pushed back near your ranged formation, in a close-packed defensive cluster. Good for a cautious approach to massed enemy hordes.

"Disperse" - All your units are spread out in a loose formation (a lot like what happens already). Good for fighting AOE casters.

"Flanking" - Your units are spread more or less evenly between two columns, ready for a pincer-movement or a dual defense. This may only be available on some tactical maps due to space limitations.

These would add tactical depth to the combat, remove the frustration that the current, practically-random formations cause, while preventing tedious manual placement and player-AI imbalance, as the AI would be subject to the same choices. I don't know much about how coding works, so I don't know how difficult this would be to implement, but it's a very important issue to address as it is mine, and evidently several others', largest perpetual issue with the game as it stands.

I of course also think it's important to maintain "ambush" situations or surprise attacks wherein your guys get taken by surprise and end up arse-backwards all over the place, but the rest of the time a degree of control would be really beneficial.

While I see your points, I still disagree with the idea that manual setup is the best alternative. Especially when I think about manually placing each and every defender in a city attack, where I can have up to 14 or 15 units, I still think it's unnecessary. Formations give the player some input to what algorithm the game uses to place your units without making you have to place everything one-by-one.

Once again, to reiterate, I don't want to manually place each and every unit. But I think there is a middle ground between manual placement and the random mess you get now, and formations are something close to that.

after a 5 month hiatus from the FE beta....

1) I love swarm, great mechanic! Though I love an uber unit (especially heroes- please buff...hint hint) having to send some weaker support units to prevent dogpiling makes sense

2) totally agree with the map sizes larger.  Its ok if a charging cavalary unit can get across the map, but it cheapens the advantages of mounted and ranged units.  

3) Agree with a 'lineup' section- this could even be as simple as allowing us to change the order of portraits in the 'army selection screen'.  IE The first 3 units are the front line, the second 3 units are the back line, etc

4) Make 'advanced lineup' a commander trait: ie a high-level commander with a 'Brilliant Strategist' ability gets to place his army AFTER the opponent places his pieces in order to exploit weakness in the lineup.

BTW great for all the hard work Stardock.  This game is shaping up to be a life-ruiner.   

why not add the feature to predefine your combat positions? i mean this should work if YOU are the attacking party or inside your city while being attacked. logically if you attack someone you would create a strategy and formation beforehand and if you're being attacked at your city you had also see time to order the formations. problem solved!