Drop Turgruk. You need him to fire 10 times for him to have the same effect as Franz. The only upside to Turgruk is he’s also dark, so will add to the dark tile damage, and his stack is permanent whereas Franz’ lasts for 6 turns. However, keep some mana pots on hand and it’ll never be a problem. I doubt you would need Franz to fire 4 times over the 90 second duration to have his effect pretty much constantly on the titan.
Depends if you want to play cheap (no items) or think about a Mythic titan with all out item bombardment.
Turgruk without items is rather pointless, but great with items.
Deadboot is nice to have but not essential.