Great discussion going on here! On a second reflection, I remember them stating in a video that they loved Final Fantasy Tactics and Tactics Ogre (me too!), so maybe it’s less equipment and more job focused. Perhaps you need to craft certain weapons to obtain a certain job, in the same way a mason crafts a hammer that someone can equip to become a blacksmith. Really, I would just love the idea the walls and towers are useful because it makes your archers more useful and defensible.
The other thing I was getting at that would be awesome is ensuring your troops or armory are equipped to deal with a variety of enemies. For example: let’s say trolls attack. Trolls, as we all know, have thick skin and are most easily damaged by fire. Therefore, you could perhaps more easily stave off this invasion when your archers have pots of pitch and torches by their stations, or if your veteran soldier happens to have a runed blade with fire damage. Also, perhaps longbows are fairly ineffective, yet since crossbows have more piercing power, they could be useful despite that naturally thick hide.
Additionally, wouldn’t it also be cool if soldiers gained knowledge from fighting or training? Say we have Grisly McVeteran from above. He knew to use his awesome fire sword, because he’s fought trolls before. But perhaps he hasn’t learned enough yet to know that a fire spear or axe would have worked even better due to the thick hide. And further still, perhaps Noob Greenhands really didn’t know what he was doing and grabbed a quarter staff and promptly gets crushed by the trolls for being slightly annoying. Then, after the attack, we would learn to put future rookies to training with Grisly to learn the benefits of burning, pokey things in Troll Lore 101. Awesome, methinks.