Yeah, one of the Pact Boon options is Pact of the Chain, where the Warlock gets a special Familiar that can attack and has a higher DC. An Imp is a popular option, because it has Devil’s Sight, can fly and turn invisible at will, can polymorph into different things and has a poisonous sting. I’d thought about that, because one of the Invocations The Warlock can get while having the Pact of the Chain allows him to always heal the maximum dice roll, rather than having to roll, as long as his familiar is within 100 ft. Since the reason he’s delving in to these strange powers is he doesn’t want to die, that would be a great choice.
But Pact of the Blade might be too good to pass up for an Eldritch Knight/Warlock. He’d be able to have any weapon at any time, dismiss and summon it at will, and the new Invocations means he could Smite with it by expending a spell slot like a Paladin, or even get an Improved Pact Weapon, which makes it +1 and has the ability to become a bow or crossbow as well.
Roll play would be easier with the Familiar. Combat would be easier with the Blade.
The problem I have is that Titus already has access to half of each of the boons. As an Eldritch Knight, he can bond with a weapon and teleport it to himself. The Pact of the Blade will allow him to also always have any weapon he wants, and be able to Smite with it.
With the Ritual Feat, he can already do wizard rituals, which is most of them, but with the Book of Shadows, he’d get 3 more cantrips and access to all Rituals. This is my least favorite option, because reasons.
And he already has a Familiar, but the having an invisible flying familiar can literally break exploration or scouting quests.
I don’t really need to pick now, obviously. Earliest would be next level, and who knows how long that’ll take. But I can’t help pondering character advancement.