Lenneth has spent a lot of time as a human, and even more time as a goddess. But that doesn't mean that there haven't been certain influences in her life. As Platina, it was seen that she found the Weeping Lilies beautiful, so we can assume that she liked flowers. I believe that this trait would have carried over into Lenneth's personality. Or perhaps, it was originally Lenneth personality that seeped into Platina's.
In
official (promotional) art we see Lenneth, Silmeria and Hrist by a waterfall as though they were swimming or bathing. I like to think it can be both. After all, as goddesses, why can't they enjoy a fresh water bath or swim in a lake? This also makes me to believe that Lenneth would be a young, nature loving, individual.
Lenneth also enjoys music, who doesn't after all. With the kind of person she is, I think piano music, harps and lyres would the the types of instruments most interesting to her. Instruments that produce soft and melodic sounds.
AND finally, Lenneth is incredibly ticklish. Backs of her legs, her feet, her arms and shoulders and back, all ticklish. No one would normally have the opportunity to discover this particular trait though because she's usually covered in armor or fighting. And no one would try to tickle a goddess in the midst of battle. Or ever really, unless their goal is to lose a limb or their head.