The titles I have:
Tyrian Grandmaster Cartographer (100%)
Canthan Grandmaster Cartographer (100%)
Protector of Tyria
Protector of Cantha
Favored (3/5)
Unlucky (2/5)
The titles I respect:
Tyrian Grandmaster Cartographer. I've walked my E/Mo everywhere in Tyria with henchies before titles were even introduced. I've spent hours in Ruins of Surmia running ahead of the suicidal Prince Rurik to make sure he lived and I mapped. I've walked the Dragon's Gullet solo, I've backtracked through all of Hell's Precipice after killing the second copy of Undead Prince Rurik and I've cleared the Thunderhead Keep all the way to the Mursaat portal. I had that title the day it came out, 4/26/06, and it's the dearest one to me.
Though I am a PvE player and hardcore PvP does not appeal to me, I respect the Gladiator title. It takes either great luck (Random Arenas) or great coordination (Team Arenas) to obtain. Even though there have been issues with it in the past where people could cut corners, many other titles had their exploits last longer and do more damage to the reputation of the title, like Drunkard and Survivor.
Buyable titles don't impress me, and neither do faction farming ones. Part of it is in the mindless repetition of the same activity, and part of it is that the titles aren't accessible to people who play casually. Faction farming titles have the additional problem of becoming utterly useless in future chapters, where no one will remember the grinding donation system ANet put into Factions as nothing like that will ever be introduced again (one can only hope). For a similar reason, the Protector of Cantha title is something I despise even though I have it, and I hope the game mechanic that makes it so despicable - faster mission completion for extra reward - disappears tracelessly from Nightfall.
I know I'll never max all titles, so I've resolved to get at least one level in each title track I have already started on. I'll have to pick something to max for Kind of a Big Deal, of course, but I can always wait for Nightfall and explore that fully, since it is something I believe I will enjoy greatly