I'm creating this topic for Max Warlorder since he asked about it in the Balancing for Beta 2 thread.
My preference is to break all units into one of the following categories:
A) Heavy infantry/Military types: (Heavy infantry, Dwarves, Pikemen, Siege units etc)
B) Light infantry/Militia types (Scouts, Light infantry, Archers, Orcs etc)
C) Large Creatures (Giants, Minotaurs, Unicorns, Elephants etc)
D) Cavalry (Light Cavalry, Heavy Cavalry, Wolf Riders etc)
E) Monsters (Spiders, Ghosts, Serpents, Devils, Demons, Elementals etc)
F) Fliers (Bats, Griffons, Pegasi, Dragons, Archons etc)
Then for each category define a movement range. In each category there can *possibly* be one exception to the category to define a unique unit (for example, scouts are the exception to the light infantry category so they can get a movement range outside normal range for that category. Wizards would be another exception to the Monster category). This makes adding new units easier to balance.
Warlords I had in general much slower movement rates than Warlords II. The result is that in Warlords II almost all combat tends to take place in cities. This makes the city bonus overwhelmingly valuable compared to all other bonus's. So I think Warlords I did a better job with movement rates than Warlords II because in a well balanced game there should about a 1-1 ratio of combat outside of cities and in cities.
Two KEY factors in selecting movement rates:
1) Boat movement rate
Boat movement in Warlords I & II was fixed at 20. This meant that the more you reduced other movement speeds the better/more valuable boats became because of their 20 movement rate and because water move only cost 1 pt like roads in the open water and 2 next to shore.
2) Vectoring
Vectoring dramatically reduces micromanagement/speeds up movement. So again, the more you reduce movement the better vectoring becomes.
What happened in your Warlords II scenario is that you can't edit boat speed nor can you 'turn off' vectoring. So as a result what happens is that the loss of a city often means the enemy can vector in armies faster than your own armies can walk from the nearest city to counter attack. That's very bad for balance. Despite your feelings on vectoring, it's here to stay and so has to be accounted for when designing movement rates.
My Preferences (based on playing Warlords I, II, III and IV):
Heavy Infantry Category:- 8-11 move
Light Infantry Category : 12-14 move
Large Creatures Category:- 14-18 move
Cavalry Category: 20-24 move
Monster Category: 12-18 move (biggest category of creatures to classify so needs a wide range)
Flier Category: 16-22 move
These rates let units move reasonably far relative to boat but at the same time not so far that they can jump from city to city without ever spending turns outside a city.
One last word on vectoring. In Warlords II it's 2 turns - any distance. Warlords III introduced timed vectoring. That means it's 2 turns minimum but can range as high as 5 turns based on the distance between the start and end city. This reduces the overpowering advantage of vectoring especially when you capture a city behind enemy lines where it takes 4-5 turns to get units. It would be a welcome addition to Warlords II (In Warlords III its a game option you select, 2 turn vectoring or timed vectoring).
KGB