Hey Gene...
Hey, my boss is named Gene. Is it...is it you?
My brother was having the same problem up until a few days ago. It was either all homers or singles...but nothing in between.
We're Timing Only also, by the way.
I suggested he find a good spot for the pitch speed slider. Oddly enough, he had to raise it from 2 to 3 (though this is the exception to what usually helps people).
This...and plenty of practice.
When you're sitting fastball, because you KNOW it's coming, tell yourself, "I'm all over this pitch! And I'm swinging early!"
Sometimes, 'just early' or 'just late' timing isn't a bad thing. It really helps hit diversity.
Utilizing 'pitch history' also helps. Press select, and take a look at the CPU pitcher. If he's alway working the change away, when ahead to righties, start looking for that pitch in that circumstance. This can allow you to sit on the ball, not to mention see it clearly as it's released, and put good wood on the ball. These often result in wall balls, or gappers.
If all else fails, and I mean ALL ELSE (at least 20 games), you could lower your power and or fielder run speed a click. Dropping power could turn a wall scraper homer into an off the scoreboard double. Also, the wind slider is one some people are dropping, but not all.
Anyway, once your misses per game, fouls per game, strike outs per game, and hits per game look good; you'll have plenty of extra base hits.
That, or play a game at Citi Field. That is the place where homers go to die.