One of the first things I do when building is:
Use a high power metal geared servo
Lose the servo saver
Change both the front axle and knuckles to aftermarket item
This one
http://www.ebay.com.au/itm/Tamiya-1-...71119127941%26 appears to be well made and does not suffer with the massive amount of slop the Tamiya system has.
I do not use any ball joints rather use propper M3 tie rod ends.
These are what I have used:
http://store.rc4wd.com/M3-Medium-Str...0x_p_3234.html
The last item is the servo horn, I either use an aluminium one or a good solid plastic one (the ones that come with the Tower Pro servos are fine).
Can be a pain to align the steering, but once done all steering issues are resolved. Very precise and quick to react. I have it in my racing truck and believe me at the speeds this thing gets to you want quick response and no slop in the steering.
If I get a chance will take a couple of pictures if that will help.