I don't know if I am understanding your question correctly.

I read 'ci(' as change what's inside parents. I read 'ci{' as change inside braces. 'ca(' and 'ca{' grab the parents and the braces as well.

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These combinations work for (d)elete as well. If your cursor is over the 4th letter of a 6 letter word, 'dw' will delete to the end of the word. 'diw' on the other hand will delete the whole word. (I've never tried 'daw' although I know 'da(' works)