I'm a long time lurker and avid supporter of the Fallen Enchantress redo of Elemental. Like many have said before, it's a huge step up from War of Magic.
One thing I noticed that may not have been mentioned enough: mobility is king. Cloudwalk is a great example, but I'd like to ignore that for this post and focus on # of squares a unit can move a turn. Cloudwalk is its own thing because it costs 80 mana and abuse of it assumes that you have sufficient mana, that you have only one stack that can accomplish tasks, and that there are few interesting objectives that don't border your kingdom.
To the point: I'm not sure if high mobility is strictly a good thing or a bad thing overall, but it is certainly something to consider in the balance between champions and other units, balance between computers and players, and overall game flow. Even if I had a stack of 9 units with crazy damage and tanking potential, I would still prefer the lone champion with moderate damage and little tanking potential if the champion can move 5 or 6 while the big stack only moves 2 spaces.
The benefit of mobility is manifold.
1) There's the freebies to collect
2) There's the fact that you can fight multiple battles in one turn
3) There's the element of surprise
4) Defending multiple locations with the same stack
5) The difficulty in mounting a significant defensive force for cities and the ease of riding into and capturing an unprepared town
My late game heroes moving 8 squares a turn can crush a town or two, defeat an NPC's wandering stack, pick up a quest, kill a wandering monster, and not break a sweat during one turn. It's mobility that makes a group of champions go from awesome to overpowered.
I noticed that there was a balance change recently that movement bonuses from similar items went from not stacking to stacking. So 3 people with a compass gave +3 instead of just +1. I like that no item is "wasted", but that's also a tremendous advantage. The most useful things in the game are mounts, compass magic item, movement boots, scout class with +1 movement and +1 sight, fast advantage, movement spell, and cloudwalk.
Making a suggestion about what to do is a little harder. Mobility makes the game fun, and I get frustrated with heroes that only move 2 squares. Here are a couple of options, though:
1) Reduce the amount of ways to get additional movement
2) Make all bonuses to movement affect the army or just as easy to acquire for trained units, so that there is no mobility reason to have only heroes
3) Make some +movement items only affect the tactical map
4) Reduce the value of mobility by increasing the "cost" of each battle (more hit points lost, end of turn, etc, so that fighting 5 battles in one turn is never a good idea/possible)
5) Increase the defense of a town so that there is no reason to blitz it with a small force
6) Add in zone of control on the strategic map and add in more choke points
7) Greatly increase the cost of non-open terrain movement (forest, hills, mountains, and especially mountainsides)
8) Have some movement bonuses dependent on control of the land. So you might get +1 movement in lands you control, +0 in neutral, -1 or -2 in foreign controlled lands
9) Have item weight impose a movement penalty so the knights in full plate with two hand swords don't run as fast the thieves in leather with daggers
10) In addition to the above, the "base" movement should be increased to 3. Then, +1 movement would only give a 33% increase in utility instead of a 50% at the start of the game
Essentially, I would like to see the boring movement choices like crossing your own territory reduced and create actual movement choices in interesting situations like picking between either crushing an NPC stack or making a risky strike at their town while leaving your own kingdom undefended. I want to be able to add in additional units to my stack mid game and late game without crippling my ability to move around the map.
I'll report back in after the next patches balance changes, but I suspect that mobility will remain king.