Ascender Absolutely Necessary?

Font nube calling on the sage wisdom of more experienced type designers… I’m creating an all caps and small caps font that doesn’t include any characters that rise above the caps height… Should I still include a separate ascender line in my vertical metrics or can my caps height and ascender be the same? On a related note, do diacritics typically sit above the ascender or below it?

They are needed to calculate the line spacing. Have you read this:

And handy tips for all-caps fonts: