is there some sort of instruction you're supposed to use to get your taker to at least get a shot on target? my first choice has a rating of 20, but scores 1 or 2 at best every season. doesn't set up many from indirect either.
Setting a left-footed player to take right side free-kick or vice-versa (right-footed player to take your left side free-kick) is always a good idea. Of course you need to take into account other attributes like technique, and free-kick taking (if your player has a really good attribute in long-shot that will be a bonus).
You might also want to set your free-kick direction to 'best header' if you have strikers with good aerial ability. Just my 2 cents.
If you have Matias Fernandez in your team then you don't need to worry about these things.. =D (I'd say 6 out of 10 direct free-kick he takes for my team means goals)