To free up the X I have been doing a few things...
The First thing is trying different bodies...I find that the LTC-R really helps the car finish. Although the LTC-R does reduce intital steering, but mid and exit it is great.
I also have tried less rear toe, which seems to help, but I usualy end up back at three deg.
I make sure my rear camber links are pretty flat. This tends to help the car rotate.
I know it seems odd, but I remove the rear sway bar. I find that on carpet the rear sway bar makes the car feel more planted. My buddy Syndr0me really does not agree on this one.
Take out the center brace above the steering rack, this makes a big difference.
The amount of traction compound you use in the front really affects the car's ability to rotate. Try playing with more or different doping methods.
It really comes down to weight transfer, the X requires that more weight gets transferred to the front. I feel the opposite with the worlds. The perfect car would honestly be a something between the two of them. I think the battery position would make a big difference and is something that I am going to be testing here soon.
Hopes this helps...