There's 16 title NPCs, though that's not the full extent of titles. Few other sources like the MMM moblin, etc.
I've been debating making an addon that reports overall completion of things like missions, quests, ROEs, titles, and other content that's easily trackable, but my motivation has been low since I already did 99% of things myself and was max rank anyways.
The title component is probably the most difficult, not in terms of technicality, but just in workload as it involves mapping somewhere between 1100 and 3000 flags to specific titles you need to manually parse and lookup in the resources as it's not exposed how the game does it. It's not complicated, just essentially writing down the menu titles and cross referencing it with the packet and the title ID, then making a mapping table so you can record which ones you have as you check each NPC.
I'm kind of lazy, but I could try to make the effort to do the work if there's enough demand. At least for the titles part for now. It also would probably basically just be a list of missing titles without trying to categorize where they were from or anything.
I wouldn't expect it super quickly though, I have a habit of getting distracted and my motivation for personal projects is in flux depending on how work is going and how burned out I am on coding at the moment lol.