Indeed, as most things you like, there is never a particular reason but that you like them.
Thank you for the insight of the Japanese people relationship with kanjis. Though I know it is not the same, I have favourite words in the languages I know (and unfavourite ones!), words that I like for the sake of their sound or letter structure.
Thank you also for this one, 永 is indeed a beautiful kanji and forever will be.
I also do love 卵 (much more than 玉子, which is clarifying but not quite as compelling) and also find that possible origin funny, se non è vero, è ben trovato.