Xeviat
Dungeon Mistress, she/her
I think if you look at PotB the way I do, it's a lot weaker. How much benefit would you give to a melee version of the Eldritch Blast cantrip? Not very much I suspect. Especially if you have taken agonizing blast, eldritch blast is a 1d10+Cha attack with Cha to hit, and you get multiple attacks with it automatically. If eldritch blast is a fair cantrip, then a melee eldritch blast would be as well.
For a long time, I've wanted to remove the current blade invocations and make PotB give you a melee weapon with Cha as the attack stat, have attacks scale at 5th, 11th, and 17th like EB, and allow it to be used as a focus and to perform somatic components for warlock spells. Its then akin go the Agonizing Blast invocation, an extra cantrip (melee eldritch blast, but up to 2d6 damage for a greatsword), without hurting their ability to cast spells. I might even consider some kind of AC bonus, but I wouldn't want to make PotB the choice option.
For a long time, I've wanted to remove the current blade invocations and make PotB give you a melee weapon with Cha as the attack stat, have attacks scale at 5th, 11th, and 17th like EB, and allow it to be used as a focus and to perform somatic components for warlock spells. Its then akin go the Agonizing Blast invocation, an extra cantrip (melee eldritch blast, but up to 2d6 damage for a greatsword), without hurting their ability to cast spells. I might even consider some kind of AC bonus, but I wouldn't want to make PotB the choice option.