A difficult part of writing for me is when a single sentence–especially dialogue–contains two tones. It sounds best as a single sentence, but ending with a period, or alternative punctuation, looks wrong. As well as this, using two sentences also looks wrong.
I can’t think of a great example right now, but I know I’ve wanted punctuation that doesn’t exist before. I’ve had moments where it would have been so useful to have a “;!” and a “;?” mark.
I actually just started working on a post, and wouldn’t you believe it!
“And that’s great;! But nobody’s as weird as I am.”
The first half is intended to be an exclamation, but the rest of the sentence is spoken neutrally. It can’t be split into two as leading a sentence with “but” is bad practice. It just doesn’t look right any way.
Ah, if only we had a line above a comma…