I love warmaster because how the army looks on the battlefield. I currently have three armies, Kislev, Dwarves, and Khemri. Kislev i bought because of the bears. Dwarves i bought because i got a good deal at an auction at a gaming convention once. Khemri was actually my first army and it is a great all around army. I currently have components for three more armies: High Elves, Skaven, and Lizardmen. High elves because the model line and the list is great. Skaven because i love the fluff and a horde of rats seems awesome. Lizardmen because they are my main Fantasy Battle army.
I build each army to 3000 points, with a core of 1500 points and 3 500 points additions, one for open field battles, one for besieging, and one for defending in a siege. These after all are the common battles for armies. Army components for open field battles are cavalry, chariots or large monsters. Army components for besieging are armored infantry and artillery. Army components for defending in a siege include archers, artillery, and flyers. I think flyers are important in defending in a siege because they can sally forth and take out enemy artillery. Thus it appears to me an all around army should be able to do all three. An army should also have a flyer mount so a hero can assist in an open field battle, in attacking defended units, and to sally forth with flyers. An all around army should have all four: flyer mounts, offensive units, besieging units, and defending flyers.
Here is my review of the different warmaster currently available.
Araby: flying carpet mount, knights & elephants, armored infantry but no artillery, and flying carpets.
Bretonnian (tournament list): pegasus, knights, trebuchet, and pegasus knights.
Chaos: dragon, knights & dragon ogre, armored infantry but no artillery, and harpies.
Demons: wings, steeds of Slaanesh & beast of Nurgle & greater demons, no armored infantry or artillery, and screamers of Tzeentch.
Dark Elf: manticore, cold one knights and the war hydra, repeating bolt thrower, and harpies.
Dwarves: no flyer mount, no cavalry or chariots or monsters, armored infantry and cannons, and gyrocopters.
Empire: griffon, knights and steam tank, no armored infantry but lots of artillery, but no flyers.
High Elves: eagle and dragon mounts, knights and chariots and dragon rider, bolt thrower, and eagles.
Kislev: no flyer mount, knights and bears, no armored infantry or artillery, no flyers.
Lizardmen: no flyer mount, cavalry and stegadon, kroxigors, and terradons
Orcs & Goblins: wyvern, boar riders and wolf chariots, black orcs and ogres and rock lobbers, but no flyers.
Skaven: no flyer mount, doom wheel, stormvermins and rat ogres and warp cannons, but no flyers.
Undead Khemri Tomb King: dragon, chariots and sphinx and bone giants, bone thrower and skull chukka, and carrions.
Vampire Countt: winged nightmare, knights and black coach, grave guards but no artillery, and no flyers.
The armies in bold have all the requisites, the italicized armies do not. I would rate them further as follows:
Top tier: High elves
Second tier: Bretonnian, Dark elves and Undead
Third tier: Araby, Empire and Chaos
Fourth tier: Demons, Dwarves, Lizardmen, Orcs & Goblins, Skaven, and Vampire Counts
Fifth tier: Kislev