If that's really what you think of medieval combat i suggest you do a little research, you may be pleasantly surprised.
Hmm, I was going to try to defend my argument, but, in light of your pleasant signature I've elected to take the advice, and do some research instead.
http://en.wikipedia.org/wiki/Medieval_warfare
The experience level and tactical maneuvering ability of medieval armies varied depending on the period and region. For larger battles, pre-battle planning typically consisted of a council of the war leaders, which could either be the general laying down a plan or a noisy debate between the different leaders, depending on how much authority the general possessed. Battlefield communications before the advent of strict lines of communication were naturally very difficult. Communication was done through musical signals, audible commands, messengers, or visual signals such as raising a standard banner or flag.
The infantry, including missile troops (such as archers), would typically be employed at the outset of the battle to break open infantry formations while the cavalry attempted to defeat its opposing number. If the cavalry met foot soldiers, the pikemen would engage them. Perhaps the most important technological advancement for medieval warfare in Europe was the invention of the stirrup. It most likely came to Europe with the Avars in the 7th century, although it was not properly adopted by the major European powers until the 10th century.
Okay, let's make a Dwarf-Checklist.
[√] Diplomats/Command structure (I suppose it would be nice to see a command structure be involved in signaling...)
[ ] Signaling System
[√] Ranged Weaponry
[√] Battlements for Ranged Weaponry
[ ] Cavalry (currently can't be used by your dwarfs)
[√] Pikemen (granted, I'm not sure it actually helps them fight mounted targets.)
Hmm, well, those things do sound nice. Let's keep digging.
Building fortifications [Castles, Walls, Battlements, etc.] was a good way to provide refuge and protection for the people and the wealth in the region...[snip]...The ability of the heavy cavalry to dominate a battle on an open field was useless against fortifications...[snip]...Building siege engines was a time-consuming process, and could seldom be effectively done without preparations before the campaign. Many sieges could take months, if not years, to weaken or demoralize the defenders sufficiently...[snip]...In the Medieval period besieging armies used a wide variety of siege engines including: scaling ladders; battering rams; siege towers and various types of catapults such as the mangonel, onager, ballista, and trebuchet. Siege techniques also included mining in which tunnels were dug under a section of the wall and then rapidly collapsed to destabilize the wall's foundation. A final technique was to bore into the enemy walls, however this was not nearly as effective as other methods due to the thickness of castle walls...[snip]...[The] use of machicolations and murder-holes, as well the preparation of hot or incendiary substances [was employed]. Arrow slits, concealed doors for sallies, and deep water wells were also integral to resisting siege at this time. Designers of castles paid particular attention to defending entrances, protecting gates with drawbridges, portcullises and barbicans.
[√] Ability to construct traps, and such.
[√] Long Sieges
[ ] Siege Equipment
[ ] Ability to dupe/confuse Seigers
[ ] Siege Sappers (Digging goblins and such)
http://www.bay12games.com/dwarves/dev.html
Military
Dwarven armies
Ability to send out fortress dwarves to lead larger groups of surrounding dwarves out around mid-level maps (or just go alone)
Ability to send equipment and fortress dwarves out to train surrounding dwarves
Ability to attack sites and entity populations with your dwarven armies
Ability to set fires and select supplies to haul back when sacking a site
Villain interactions
Must adjust villains etc. to allow them to operate at dwarf mode time scale
Make armies/beasts that attack fortress come from actual groups moving on world map
Ability to fight other armies with your dwarven armies
Larger armies should spread over multiple mid-level map squares
Ability to create fortifications/lines/etc. instead of spreading haphazardly
There are complications to be worked out if you can zoom in to battles and control them at the local level, concerning what happens to your fortress
If you can zoom in, situations like being surrounded need to be respected and have the desired results regardless of what area is zoomed in on
Allow villains to attempt to demand tribute from you
Improved sieges
Eliminate remaining edge-of-map exploits
More highly trained attacking soldiers when approprate
Many trap exploits are handled above by requiring more to produce a trap, things like cage traps should make more sense vs. large creatures etc. (respect
strength/ability vs. material, large cages might be separate object)
Coming up with a plan to overcome pathing obstacles to reach fortress innards
Ability to dig (optionally, default on)
Ability to build bridges/ramps
Ability to use grappling hooks/ladders/climb
Learning from mistakes if first attempted assault plan fails badly
For instance, if many siegers are killed, caged, etc. in a given hallway, they shouldn't generally go that way again, even if that means building/climbing
/digging
Siege engine improvements depend on state of boats, lifts/moving fortress sections, since these should all use the same framework
Other resources I'm not going to bother quoting, b/c it would get a bit lengthy:
http://deremilitari.org/primary-sources/ [√] Varied armor and weapons (however, more could always be added:
http://en.wikipedia.org/wiki/List_of_medieval_weapons )
[ ] Watercraft
[ ] Ability to siege others
Well, I have to say there is room for improvement, no doubt, but I do have to mention my awe at just how broad the ability we already have in this regard is. I'm sure I've missed some things, but for a couple hours research I think this serves as a relatively good sample of what future dwarfen military strategy could include.