I understand you would like to give your world some original nuance, but I cite the old say: "jack of all trades, master of none".
This is true also for weapons. The most lethal and effective weapons are those that are
optimized for one kind of usage (to put it simply)
easy to learn to use effectively
#1 allows to optimize the weapon in itself, #2 allows optimizing the training of a large army with less economical effort, hence optimizing the overall effectiveness of a group.
There is a reason why in all history most armies where composed by troops specialized with a single kind of weapon. In the cases where you really needed more versatile troops (such in more modern warfare) you had a set of different weapons each optimized for a different purpose.
For example, the ancient rome soldier had a gladius for melee and the pilum for one-shot ranged attacks.
Another example: in modern warfare the typical soldier have an assault rifle for normal mid-range operations, a pistol as sidearm and an assault knife, and probably some grenades. In a platoon you could have more specialized troops, for example those able to use an RPG or a stinger missile.
In general Swiss-army knife sort-of weapons are more difficult to use and to train to use effectively. Moreover, once the weapon breaks, you loose all your offensive capability, whereas if your sword breaks you could always use a dagger or a bow to be still useful on the field.