Aside from the outdated argument for morality, he came up with some decent arguments, namely the contingency, the prime mover, etc. The problem is, for each argument he arbitrarily posits God as an explanation. For example, he argues for the existence of something non-contingent, otherwise if everything had the ability to fail to exist, there would be nothing in existence. The logic is sound (almost) but all it does is argue for something, anything non contingent, and there is nothing to suggest that must be a God.
So in light of that, I don't see anything all that convncing about his arguments.