This is probably the "safest" definition of God. It avoids all the pitfalls of the gods we know about (Yahweh, Zeus, Odin, etc etc.) which carry with them very specific features which impinge on reality in such a way as to be "testable".
The "God-as-Creator" concept is great because before the universe existed (and "before" time itself) there is no way to know from whence it all came.
THIS I can accept as being "agnostic" about since there's no way to test or falsify or even comprehend what it means. Clearly the Universe appears to have a beginning in the big bang but what was there before the big bang? Some believe the universe could exist in a state of eternal bigbang-inflation-deflation-bigcrunch type cycles happening over and over again. Others believe that M-theory (Membrane Theory) has that these Membranes exist and when they intersect or touch a Big Bang is set off and a new universe pops into existence. Others believe there is a mind behind it all.
But, that being said, if "God" created the universe it does not tell you much about what God actually WANTS or NEEDS from his creation if anything at all. The religions of the world simply make up stories about what they THINK God wants and tell people it IS what God wants. If anything if you look at the Universe as God's handiwork you might infer that He is antithetical to life because the vast vast vast majority of the universe would not support life. Which kind of gums up the works when one translates that to a "personal God" concept.