Kind of liked the earth element better it's not as over done as lightning and it's undervalued I believe. And it actually fit his traits and stats. Oh I hope for a long lasting story good luck.
I like the novel as it is, good writing and interesting story. About MC, he was kinda naive at the start, now its better. I personaly like evil MC stories with R18/harem. Since he can have a human form now, well, im baited xd. Lets See what kind of story you want to write.
Have a nice Day.