In general, secular nations don't use the "God" phrases outside formal or ceremonial situations. If the recently deceased was not known to you personally you simply call them "late" plus past tense: "The late Joan Rivers / Robin Williams was .....". If you are writing something, simple past tense without honorifics is standard. See Wikipedia for many, many examples.
Even England, with its strong Christian history, makes its most important official pronouncement with no reference to any religion: "The King is dead. Long live the King."
Ben's lengthy list would be fine in a speech, most commonly at the person's funeral. Many of those terms would sound rather pompous elsewhere.
I like "Mr X, God puts him in heaven, was..." - it has a pleasant far-away-land feel to it.
"Mr X, God's have mercy for him, " is a bit too close to "May God have mercy on your soul" - a phrase to AVOID at all costs. It was often spoken by the priest or judge just before the condemned person's execution, the unspoken second part being "because we won't."