Sure but 1-The current solution is worse on this dimension. 2-Since Bitcoin Cash doesn't have replace-by-fee this is impractical for any small transaction. 3

Sure but 1-The current solution is worse on this dimension. 2-Since Bitcoin Cash doesn't have replace-by-fee this is impractical for any small transaction. 3-Most of the situations that need to be immediate are small--with the large ones it makes sense to wait.