It would kinda lost it meaning. The "Kita aura" is not just mean Kita's aura. Kita litelary translated as many joy. So it mean "aura of Joy" or something. It just get lost during translation. That probally why the artist not inclue it
That wouldn't be a problem. We've had comics with unconventional SFX like "Moko-taaaaaaan" since forever.
As for why, the author most likely just never thought of including it, but not for the reason you described.
So basically,you lost your way from the outside world?Y-yes.It was so abrupt, and I don't know what's what anymore...Is this Gensokyo's resident extrovert?!Alrighty, I'll help you out!Let's look for a way to getcha back to your former world.✩