Human intelligence is able to design and create and so we can see the properties of what constitutes design, such as order, principles, etc,....
To claim, well, we don't know what God is like so all we can do is compare human intelligence is a sham statement really. We don't really know what gravity is like either, but we know it by it's effects. We see the effects of Intelligence in the design of the universe.
I ask again: what more do you want God to do?
Send Himself as a man, His "Son", down to show us the way, be crucified and rise again? Oh yeah, already did that.
Have millions of people be touched by Him and share that with others?
Oh yeah, already did that.
Give us intelligence and creative abilities so we can see what design is like, and so understand that the world around us contains design?
Oh yeah, already did that.
The properties of design are clear, such as order, and the world demonstrates those properties.