Welcome to ANGERME, Wakana-chan!
She already has a very nice singing voice. I can't wait to see how much her singing develops after several vocal training lessons
Also, some wotas are speculating that her real name is "松本若菜", and that the kanji in her given name were changed to hiragana for her stage name of "松本わかな". There's a famous actress named "松本若菜", and they might not have wanted people to get the two confused.
Tanaka Reina did a similar thing when she joined H!P. Her real name is "田中麗奈", but she uses the stage name of "田中れいな".
There's no way to know for sure as of right now though.
Yeah, it may or may not be. Wakana is a common Japanese name, so kanji would make the most sense, but using hiragana for names that usually have kanji for originality is also a thing.