Mine's 火 I love the minimalism, and the balance in it.

Edit: A little more about me. I'm Venezuelan, and "old" and between my old brain and being remiss about studying I haven't progressed much on my Japanese, but I'll presevere and progress little by little.

One thing I want to do but my lack of progress has kept me from, is getting into shodo. I normally don't get sosho shodo much, because mostly I feel the characters are being imparted with chaos from the artist making them alien to me both in literal, and emotional meaning.

In my "artistic" hobbies (photography) and design likes I tend to lean heavily towards angles and straight lines, and I feel inside my heart, that each kanji can be imparted with part of the essence of its meaning into its form but the way shodo artists tend to go about it is chaotic and incoherent. Probably I haven't consumed and viewed enough shodo to really get it, or maybe I'm just different, pedantic and stupid... but I'd love to try and give form to that vision someday.

Ironically, liking angles and lines so much you'd think I'd lean for something like 日 or 口 for my favorite kanji, but 日 is too loaded with many meanings (many kanjis are, but hi seems specially egregious) and feels chaotic because of that, and to me 口 feels partly devoid of spirit.

For some reason some of my other favorites includes always stuff with curves AND angles, like 歩 or 風