When you set up for the IO Fh, do you quickly get up and around the ball so that you are lined up for the x-court shot? From that position you should be able to hit the x-court more naturally with you body rather with an orientation that is open too much. Your stance can be closed or even slightly open, but your upper body must be coiled sufficiently to be able to hit the x-court shot properly. If you set up correctly you should be able to hit the IO shot or uncoil a bit more to hit the ball DTL instead.
Also, see if you can hit a bit to the "outside" of the ball rather than the "inside" of the ball. Hitting on the "inside" of the ball will tend to make the ball path flare out more but this could also it more difficult to keep it in the court.