As currently swords as less usefull for melee and breaking an enemys shield, this new model of swords should make swords a more tactical decision. Back in the past, dual wield build were common around level 33, when many players wanted to use the high damage and to get around the problem of limited uses.

The new idea is that every sword can only be used per battle. As benefit, it has a special effect and its use does not require anything (neither energy nor does it cause heat to you). The damage will also remain as it is, not like in the past were swords dealt superior damage.

Energy (Blue) Sword - Drain a huge amount of energy of the enemy
Flame (Red) Sword - Cause a huge amount of heat to enemy
Combination (Golden) Sword - Drain a high amount of energy and cause a high amount of heat to enemy
Normal (Gray) Sword - Cause a large knockback (like in the old times)

So the idea is that using a sword is a tactical decision in order to break through the enemies shield. If you are unsure which kind of shield the opponent has, try the combination sword. The idea of the knockback sword is to prevent being caught in your corner, a kind of anti-charge.

i actually like this, mu vote is yes

Though I like the idea it sounds like you're trying to make it so a sword has to be part of every build and that was part of the problem at some levels before the patch. A build will have to be well thought out now if it wants to use a sword and will probably have to be a leveled sword.

In the past, the reason for the sword use was their high damage. Once it was possible to get near the enemy (around level 30, when Teleport, Charge and Harpoon had two uses), they dominated the building strategy.

In this use, it is more a tactical decision, because you can use it only once and have to give up a side wepon slot for it. So you have to ensure the rest of your build can povide enough range cover.

Currently, a sword deals less damage than stomp and nearly every sword causes heat (even the former knockback weapon, with has no additional function at all). Because the stomp can be leveled as well, it will still deal more damage than a leveled sword.

I do not think it should cost nothing for you to use them.