Historically the issues raised on the forum with adding an additional weapon skill line of this sort have been:

1. The addition of new weapon group items into all existing set loot tables.
2. The addition of new animations.

There is an opportunity to introduce sword and spell type melee Magicka without impacting the above.

The dual wield line already forms a base, it has a spam able, a dot, a shield, a ranged attack and an aoe.

The introduction of a passive in the skill line that makes dual wield cost magicka\return magicka off HS and key off Max Magicka would fit the mechanics.

For the visuals of sword and spell, an off hand visual replacer along the route of style pages could be introduced, we already have a plethora of particle effect weapons so an off hand fist wreathed in energy isn't that hard.

The last element of coding would simply be adding this particle effect to existing abilities, so for example hidden blades were wretched in energy as bolts rather than knives.

Its also marketable with different particle effect color motifs available through crown store.

Players could enchant the base off hand weapon with any desired elemental effect using the existing system.

Thoughts (other than I'd rather they fixed performance), would this fit for a melee Magicka line?