This afternoon while absent mindedly sanding a cardboard template, I realized I might have a problem. (I mean...IT'S A TEMPLATE, not the finished product)
Is it normal for the TOD to light up more with the bigger (mine are 18's) rims?
No that is not normal unless you did something unthinkable like drive the VX with different size tires or rims on front or back at any time. But no you will not get any TOD problems due to increase in wheels size as long as all 4 tires/wheels are identical.