The truth is you don't need to make anything new.. we already have almost everything you need. All you need to do is to rename, and remove spell point. Also for some spell you need to upgrade the damage/dc.
p.s. you can do this right, and we all come back and buying new pact and this class. or you can do it wrong, most of us will not come back. and you will just waste both yours and our time.
Least Invocations
Baleful Utterance - Sonic Blast rename
Beguiling Influence- grant 1/warlock level enchantment bonus to Bluff, Diplomacy, Intimidate
Breath of the Night- Obscuring Mist rename
Dark One's Own Luck- cha to save buff. last 1 hour
Darkness- Solid Fog rename
Devil's Sight- True seeing rename
Earthen Grasp- We already have this on Sorc Earth path..
Eldritch Glaive- Make this like flame weapon.. you summon a eldritch weapon that increase damage base on warlock cast level.
Eldritch Spear- Extend spell rename
Entropic Warding- Deflect arrow feat buff
Frightful Blast- your Eldritch blast have 20% chance to set enemy shaken
Leaps and Bounds- grant 1/warlock level enhancement bonus to Balance, Jump, and Tumble.
Miasmic Cloud- Mind fog rename
See the Unseen- see invisibility rename
Sickening Blast- your Eldritch blast have 20% chance to give enemy -1 peantly to all ability score.
Spiderwalk- Spider skin from druid spell rename
Summon Swarm- Enveloping Swarm from druid spell rename
Lesser Invocations
Beshadowed Blast- your Eldritch blast have 20% chance to blind enemy
Brimstone Blast- Yours Eldritch blast does fire damage and 20% to reduce enemy fortitude save by 1.
Charm- suggestion spell rename
Curse of Despair- Bestow Curse rename
Eldritch Chain- chain shape
Flee the Scene- Haste rename
Helltime Blast- Yours Eldritch blast does cold damage and 20% to reduce enemy dex by 1.
Hungry Darkness- Enveloping Swarm upgrade damage rename
Ignore the Pyre- resist energy rename
Sudden Swarm- we have similar effect in game already. from summon monser(Umbral Warg)
The Dead Walk- Create undead spell rename
Voidsense- Glitterdust upgrade rename
Voracious Dispelling- dispel magic rename
Walk Unseen- invisibility rename
Fell Flight- ddoor rename
Greater Invocations
Bewitching Blast- Enemy strike by your blast have 20% chance to become confused
Chilling Tentacles- recolor Entangle and upgrade dc/damage.
Devour Magic- greater dispel magic rename
Immunity to frightful presence- buff that grant dr 2/- every 4 warlock level.
Eldritch Cone- cone shape blast
Enervating Shadow- Invisibility, Mass rename
Noxious Blast- Stinking Cloud rename
Repelling Blast- your blast have 20% chance to knock down your enemy.
Vitriolic Blast- your blast deal acid damage
Wall of Perilous Flame- wall of fire rename
Dark Invocations
Dark Foresight- Displacement spell rename
Eldritch Doom- self center aoe blast
Impenetrable Barrier- we have many barrier type of effect.. maybe give 4 prr/mrr every two warlock level while remaining in the barrier
Path of Shadow- Shadow walk + Vigor self only rename
Utterdark Blast- enemy struck by your blast have 5% chance to recieve 2 negative level.
Word of Changing - Tenser's transformation rename
edit: All shape should deal same amount of damage as normal single target blast. Because you do have to sacrifice a known invocation for the shape.