Okay, you may just have to use a setup station to fully understand, but i'll try again

The TT02 in my opinion has minimal play, but it does exist.
I am assuming that this is like other Tamiya kits where a bit of play is actually okay, and trying to remove that play doesn't seem to work well for the kit.

The Setup station helps me measure many things other than toe in/out including camber, ride height and steering angles (what degree of turning radius I am getting on each side).

You mentioned that the wheels of the TT02 can be pushed in and out slightly about a degree. I get that and have the same experience w/ my build.
With my TT02 on the setup station what I do is turn my wheels via the controller a few times to the left and right then see where the steering naturally settles (while on the station). From here I adjust the left and right front toe. After adjustments are made and while the car is still on the setup station, I again turn the wheels via the controller a few times to each side see where the steering naturally settles and re-measure the toe in angles. In my case the TT02 kept its settings and my toe angles were set as I wanted. I believe this is because toe out for the front shows play only when you move w/ some force (in this case your fingers). So the setup station shows where the toe out falls naturally (your not pushing on the wheels w/ your fingers to move it out of whack). Sure after I took my car off the setup station I could push the toe the wheels w/ my fingers and feel some play, BUT this does not seem to effect where the car naturally centers (especially after set correctly).

-I also used the setup station to adjust camber both front and rear.

-I balanced my wheels and added puddy (not w/ the setup station)

-I weighed my car front/rear and side/side (not w/ the setup station)

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Using these tools my car went from swaying to one side (a tad) after the initial build to running a perfect line. Also my turning was equal in both directions (whereas w/ the build it was not perfect). W/ the setup station you can also measure steeering angles and adjust.

I only used my controller to adjust:
-end point steering on each side (as there was a tad of binding at full turn)
-throttle curves
-steering curves
-abs braking

I hope this helps, makes sense?

I personally feel that a setup station is very valuable when used to measure and get precise readings. It has saved me a ton of time and all of my cars are set correctly mechanically w/ very minimal tweaking needed via the controller. The only things I set on the controller are my endpoints, throttle and steering curves/delays, etc, and braking adjustments. If I have to adjust my steering trim via the controller more than about 1 or 2 clicks I always go back and see what is going on mechanically that is causing me to to adjust steering trim via the controller.

For me it is also really easy to make quick adjustments to my cars setup during a race day. Takes all of 5mins and you don't really have any other option on race day ...there isn't opportunnity to get practice sessions in between heats. You know that if your car needs more grip during a race you can easily adjust the camber to gain a bit of grip (for example) by adding a degree via the setup station. If you had to eye ball this you wouldn't get it to be precise on each side.