I've made the changes. Replaced Eldritch Blast for Minor Illusion, replaced Hellish Rebuke for Expedious Retreat, added Illusory Script and Unseen Servant to my Ritual Book, deleted 100 gp from my pouch, and got Splint Armor, which increases my AC to 19 if I'm using a Shield, which I will be. I like the flavor his current Invocations too much to change them.
I don't know if this is in Character for Titus, but I'm going to bring it up anyway. I was looking at the new Rune Knight UA from a few weeks ago, and it looks great. Lots of cool utility, though not as much as a BattleMaster. Instead of an Eldritch Knight's ability to wield spells and gain spell slots and such, it allows him to create Runes and put them on Armor, weapons or shields. Whoever wears or holds the item gets one passive bonus, usually having to do with gaining advantage on certain skill checks but not always, and a 1/Short Rest ability.
Rune Knights can also grow Large twice per day for one minute, granting them Advantage on Athletics Checks and adding a d4 to their damage.
When I get to Fighter 3, what do you think of Titus grabbing that instead of Eldritch Knight or Battlemaster? The 1/Short Rest abilities fit with his Warlock Pact Slots, which refresh on a Short Rest, so basically almost all his stuff is refreshed on a Short Rest, rather than the Long Rest that is Eldritch Knight. And learning Runes goes along with Titus' learning Rituals. And, he can let others use the items that have the Rune on it. He gets 2 at lvl 3, 3 at lvl 7 and 4 at lvl 10, which is likely as high as he would go, though he can get 5 at lvl 15. However, he can only wear one suit of armor, wield one shield or weapon in one hand and a weapon in the other, so he can only ever use 3 himself. He'd have to give the forth and/or fifth to allies.
I'm imagining him, once he gets Plate Armor, going into battle wielding a shield and a shadowy Singing Axe, with the Armor, Sheild and Axe having ancient Runes on him, then growing Large and casting Armor of Agathys, while activating the Hill Rune, which grants resistance to bludgeoning, slashing and piercing damage for one minute while he's large (which increases the use of Armor of Agathys), and becoming the Avatar of what (at least what he thinks) his Patron looks like. Yeah, that would take a round or two to set up, but still, the look is awesome.
I will likely do Warlock 3 next, but after that I want to do Fighter 3 to get the Archetype, so I've got probably about a year to figure this out, lol. At that point, the only options I'll have are Warlock or Fighter on a level up, but I just can't help character building.