A God-who-is-a-person would, like us,
Be composite, and thus exist above
The Ground of Ultimate Reality,
And, so, could not, in itself, be its own cause.
The above composite God, complete with a planning
system and an emotional
system, seems to be a problem in very many ways. See
http://whywontgodhealamputees.com/god-toc.htm A God-which-is-not-a-person would be
The Ground of Ultimate Reality—
Strings, Energy, Awareness, whatever—
The source of which forms/is our reality.
You could even call it the Ground of Determination (G-O-D or G.O.D.) and then at least it would have a single meaning.