Blue
Ravenous Bugblatter Beast of Traal
As for the guy who seems to think that you can make a hand crossbow into a pact weapon, review the text: "You can choose the form that *this melee weapon* takes each time you create it...You can transform one magic weapon into your pact weapon by performing a special ritual...it appears whenever you create your pact weapon thereafter."
That looks like a misunderstanding. One poster was talking about pact blade in one hand and crossbow in another with the crossbow expert feat, and then others replied to bring up information agreeing with you.
A high dex warlock with a pact rapier and crossbow and hex to add damage to the extra attack as well would be potent in melee, though since we're talking feat investment we could compare with warcaster to use EB in melee range. Hmm, I wonder where the math falls at various levels for that assuming Thirsting Blade or Agonizing Blast as appropriate.