I have been thinking of what flavour items and achievements would make a character of your class truly a member of said class. For the Druid class I have come up with some (fairly obvious) things.
What about your class? Which items, titles, mounts, achievements exist in the World of Warcraft which a true master of the class would possess? How would you go about getting them today?
Kallixta has not been a Paladin long, but she knows her dream and her idols.
One title fits with the Way of the True Paladin more than any other, Crusader. It shows that one is dedicated and has persevered to be a Champion for all members of the Alliance or Horde. While other classes can earn the title, Kallixta feels a Paladin should be expected to earn it.
It would also be appropriate for a Paladin to earn Kingslayer, ending the threat by the best known former Paladin.
Paladins have their own warhorse. Why should they choose anything else? Well, there are mounts that will take a Paladin to where they are needed quicker or by air. It should still be battleworthy, something suitable for charging into the fray. It could be argued that a war mount earned in the battlegrounds, such as a
Black War Steed, or maybe the Armored Brown Bear of Dalaran is acceptable, but that would apply to any of the other war horses and none charge any quicker. To be faster, the Paladin would need a flying mount. The quintessential Alliance flying mount for a paladin would be any of the gryphon or swift gryphon mounts. The Armored Snowy Gryphon isn't any faster than the other swift gryphons.
Those are the practical answers, but are there mounts that represent something beyond the practical? A mount earned at the Argent Tournament speaks highly of a Paladin's past efforts, especially the Argent Charger or Argent Hippogryph.
There are few achievements that appeal to Kallixta as essential to a Paladin's nature. One aspect that may not be part of every Paladin's experience, but is to Kallixta, is service to others. A Paladin must be useful to others, sacrificing something to improve life for the many. It is in keeping with this vision of Paladins that Kallixta expects to earn the Looking for More and other achievements in this chain. Grouping as the Tank or Healer with the LFD tool has always been part of her experience. I suppose that means the title "The Patient" belongs in the above Title paragraph. Conversely, the achievement associated with "The Crusader" title belongs here.
Your mileage may vary. Batteries not included. No animals were harmed in the making of this post, except some in Azeroth and Outland while working on Pest Control, of course. Any resemblance to a true paladin, either living or undead, is purely coincidental.