Pact of the Blade additional Eldritch Invocations

[Spectre9000]

I'm thinking of adding a couple new Eldritch Invocations to Pact of the Blade Warlocks to try and improve it some as I feel it's lacking. I'd like some feedback on whether you feel these are OP or not, and any exploits you can think of with them.

Eldritch Resilience
Prerequisite: 7th Level, Pact of the Blade feature
Mage Armor cast on you now provides a base AC of 14 + your Dexterity Modifier, and grants you resistance to force damage.


Eldritch Hardening
Prerequisite: 15th Level, Pact of the Blade feature
Mage Armor cast on you now grants resistance to non-magical bludgeoning, piercing, and slashing damage.


Twin Weapon
Prerequisite: Pact of the Blade feature
As part of the same action you use to create your Pact Weapon, you can now create a second Pact Weapon and use it as per the two-weapon fighting rules (PHB, Chapter 9). Additionally, you can use two-weapon fighting even when the pact weapons you are wielding aren't light. You may also transform an additional weapon into a second pact weapon as per the rules listed under the Pact of the Blade Feature (PHB, pg. 108).


Eldritch Strike
Prerequisite: 9th Level, Pact of the Blade feature
When you hit a creature with your pact weapon, you can channel a spell of 1st or higher level into your pact weapon. The spell's range becomes touch, if it was not already, and must target the same creature hit, otherwise you can not channel it.


Souldrinker
Prerequisite: 17th level, Pact of the Blade feature
The eldritch powers of your pact weapon now heal you an amount equal to your Charisma modifier (minimum 1) with each hit.

[Regulas]

Sooo my cents:


1) Given that you'd want to take the mage armor invocation I would say this risks being too weak (unless you expect a mountain of force damage) since it demands two invocations just to fix the horrible AC warlocks have without multiclassing. I would include being able to cast mage armor at will so that way you can replace the earlier invocation with this one when you reach the level. I would also consider discussing with your DM just allowing you to gain Medium armour proficiency upon taking pact of the blade without needing to use up any invocations.

2) I'm just uncertain either way

3) Honestly I don't think this should even need an invocation, most DM's just let this be done by default TWF is already seen as being questionable to begin with, and really this just amounts to style.

4) Cool as it is this risks being a tinsy bit OP. Full attacks for the round and casting a spell, which your a warlock so that's always going to be a level 5 spell. It's also drawing directly from the Eldritch Knight. My concept Hexing Blade: When you strike an opponent with your pact weapon you can cast Hex on that target as a bonus action without consuming a spell slot. This let's you have Hex up as you need it without having to worry about casting other concentration spells or needing to waste any slots. It also stops you from abusing Hex in social situations since you need to attack.

5) It's so rare that I've ever done much at this level so I can't really say much though it does feel weak for a level 17.

[Talamare]

Too bothersome

I would say just change the Lv12 invocation to be that it heals you for CHA
Honestly, with a name like Lifedrinker I honestly assumed it would before I read it...

With this change alone it should provide Warlocks a small boon to their survivability. Not even needs AC based survival.

TWF thing, most DMs already naturally allow this and its someone incredibly minor. Your DM would need to be insanely unreasonable to not allow it.
Well, except the non-light part...