"The absence of evidence is not the evidence of absence."
Actually, as the lecturer of my critical thinking course pointed out, it depends entirely on what is claimed. Oftentimes an absence of evidence is very strongly evidence of absence. Every time I look out in my front yard, and fail to see an elephant, this is extremely strong evidence for the absence of all elephants from my front yard.
Whether it is a strong or weak argument depends on the strength of the (often unstated) premise: "If (thing) exists, then we would have evidence." This is very strong for my front yard elephant, but very weak for, say, the existence of extraterrestrial life.
So, given that we're looking for a god that apparently:
a) Designed the universe down to the last detail
b) Is everywhere at once, and
c) Loves us, and wants us to believe in him
it would seem that absence of evidence does in fact give us evidence of absence.
This of course, is not the only argument against such a being, but I thought I might defend it since you brought it up.