The chance of the nonstop BNE-DXB being replaced with an aeroplane without suites is low enough that I wouldn't worry about the risk of that happening. Australia non stop services are a pretty safe bet when it comes to the product.

Even with the service via SIN, I would still feel very safe in booking and getting a suite

Even if it did 14 hours in old 1st plus 7 in 380 business would be better than 14 hours in business plus 7 in A380 1st

The shower onboard is nice, but having a shower is hardly ( I hope ) a unique experience