Lea is still comparatively young to the average Eorzean Viera population, but that is certainly not to say he's not been around the horn a lot. His travels as a part of the troupe of entertainers when he was but still a kit helped him gain a wide variety of both skills and interests.
A sure way to strike up a conversation is to be in the know, or have at least cordial knowledge of some of Lea's interests.
Barding and Dancing
Lea is, first and foremost, following in the footsteps of his mother and father as both dancer and bard. Many in Eorzea already know him through either having seen him in many a place playing wonderful music, or at a handful of clubs dancing light on his feet. Lea's heart and soul belong to the music, in both form and in function.
The Forests
Having been born of forestborn, Lea never got to see his own ancestral homelands, but dreams about them and what they might be like regularly. His parents still spoke the Word when he was but a kit, leading to this being his first language, making his current way of speaking the common tongue sound a little peculiar, and overly formal. The aid of his first wife's soul has helped him considerably improve, but many still hear the Lea they first knew, before he met Illysian. Lea finds many aspects of Viera culture fascinating, and enjoys speaking of the forest with those whom experienced it for themselves.
Travel
In Lea's lifetime, he has never known a place to call home except the keel of a carrack or the back of a pillion. His family by the nature of them being in the troupe never had a place to call home for more than a few nights, something Lea came to wonder about as a kit, and appreciate as an adult. Given the opportunity he'll tell many stories of travel throughout his youth, and remembering (or vaguely remembering) all the places in the world he's been, and where he wants to go again.
Food and Drink
Having grown up on scraps and whatever his parents gave him, Lea has come a long way, especially with his first wife's love of cooking. He still regularly tells stories of what food was like in the very poor troupe, and how one nameday (he doesn't remember which), he got a whole loaf of bread as a gift. He always punctuates this by saying he gave the least moldy part to the younger kits. Today, however, Lea's pallate is very eager to try new food and drink, or enjoy those which he has come to love, through his own hands or through the hands of others. He also enjoys being able to critique, offer suggestions for improvement, and compliment where possible.
Magicks
Despite Lea's connection with the Mist and the rage it used to induce in him, Lea really does not have any aetheric connectivity that is noteable, nor any sort of magick skill. Thus, he finds others' connectivity fascinating, especially when they can use it to create grand displays or artwork. Lea enjoys hearing of the exploits used with aether, and seeing what magick can do, especially through his witch friends, the Fens.
Side Note
Lea's a very complex bunny, and he has a wide variety of interests, but these are the ones that are sure to get him chatting. (Plus they're the only ones I could think of right away!)