I'm homebrewing a potential subclass for use in a campaign and I'm trying to make sure I'm not making this OP. The gist is we've got a wizard with proficiency in glaives and I'm trying to make that work. Out of the box it doesn't work very well (2H weapon + spellcasting? Melee + squish? No boosts to melee combat?). The thought behind this subclass is that it'd be a variant of Bladesinger, but instead of an agile duelist type, it'd be a slow, methodical, hits-like-a-truck type. A couple features were pulled from the original Bladesinger, a couple from Eldritch Knight, and a bit from War Caster.

In gameplay, how this works out is a series of alternating turns, going for a melee attack (preferably with Green-Flame Blade which invokes War Magic and, if it hits, Arcane Strike) and then a spell on the next turn to make use of the forced disadvantage on saving throws.

Edits: TIL if you have a two-handed weapon you don't need War Caster to do somatic components. Really I shoulda known that because...quarterstaff. Also nerfing the "smite" ability on Sword Dance

Edit 2: Yup it's OP. I made a few changes and hopefully it's less so now, but it's also a lot closer to the default Bladesinger now. Functionally the only difference is the ability to swap the damage type on a single attack to something elemental.

Wizard Subclass: Sword Dancing

Training in War and Song

When you adopt this tradition at 2nd level, you gain proficiency with one type of martial melee weapon of your choice.

You also gain proficiency in the Performance skill if you don’t already have it.

Sword Dance

Starting at 2nd level, you can invoke a Sword Dance based on the elven Bladesong, provided that you aren’t wearing medium or heavy armor or using a shield. It graces you with supernatural defense, power, and focus.

You can use a bonus action to start the Sword Dance, which lasts for 1 minute. It ends early if you are incapacitated, if you don medium or heavy armor or a shield, or if you are disarmed. You can also dismiss the Sword Dance at any time you choose (no action required).

While your Sword Dance is active, you gain the following benefits:

• You gain a bonus to your AC equal to your Intelligence modifier (minimum of +1).
• You gain a bonus to any Constitution saving throw you make to maintain your concentration on a spell. The bonus equals your Intelligence modifier (minimum of +1).
• Once per turn when you hit a creature with a melee weapon attack, you can expend one spell slot to deal force damage to the target, in addition to the weapon’s damage. The extra damage is 1d8 for a 1st-level spell slot, plus 1d8 for each spell level higher than 1st, to a maximum of 5d8. Additionally, if the target is a creature of Medium or smaller size, it must succeed on a Strength saving throw against your spell save DC or be knocked prone.
• Once per turn when you hit a creature with a melee weapon attack, you may change the weapon's damage to 2d6 of one of the following types: necrotic, cold, fire, lightning, or force.

You can use this feature a number of of times per day equal to your proficiency bonus. You regain all expended uses of it when you finish a long rest.

War Magic

Beginning at 6th level, when you use your action to cast a cantrip, you can make one melee weapon attack as a bonus action.

Arcane Strike

At 10th level, you learn how to make your weapon strikes undercut a creature’s resistance to your spells. When you hit a creature with a melee weapon attack, that creature has disadvantage on the next saving throw it makes against a spell you cast before the end of your next turn.

Reverted to the default Song of Defense with no changes.

Song of Victory

[No changes]

The question is, is this OP? Weak? If it's OP/weak, what could be done to balance it? Any input would be appreciated! Thank you!