Now, that is a different animal. I think you are correct to conclude that if God exists and permits suffering for no reason, then it would be unreasonable to worship Him.
However, what you have stated is that you don’t believe in a God who permits suffering because you don’t like the idea of a God who would do this.
That’s incoherent and is simply designing a god that conforms to your own wishes.
Now, as to the part about God permitting suffering for no reason, that’s also incoherent.
As I have demonstrated, to your 5 yr old you may be permitting suffering for no reason, while she is being attacked by hospital personnel. You may even (if you are a good father) have held her down and assisted the hospital personnel–to her utter and complete horror.
Yet you know that you are permitting her suffering for a good reason. A very good reason.
So perhaps you could extrapolate that to God.