As much as people scream that she needs a solo movie because FEMINISM, it's not as if she's ever been a particularly interesting character. She works better as a supporting character in other people's movies (or in the Avengers) than she would on her own.
It's not even a gender thing - I feel exactly the same way about Hawkeye.
I'd even say the same thing about Coulson - as much as I liked the character, I don't think a Coulson solo movie would have worked. The only reason Agents of SHIELD works at all is because a) it's a TV show and not a blockbuster movie, and b) it relies almost as much on the rest of the supporting cast as it does him, and even then opinions about it tend to vary pretty strongly from person to person.
As much as Disney might love the idea for cash-in purposes, I don't think every single member of the team needs their own solo film. Save those for the major characters, and keep some of the others as minor supporting cast, and it makes the major characters feel even more important.
This so hard. ---
(\/)(\/)|-| There are precious few at ease / With moral ambiguities / So we act as though they don't exist.