Already said here. IAAF always complains that many things should be done in a short period time after the ceremonies and before the athletics competitions itself. Don't you remember the "swimming pool" (they used in OC) issue in Athens 2004???
But two cauldrons in two different places. The first time they used a indoor stadium for the ceremonies (IOC approved too!!!!)
Let's hope not... But it's not up to us this decision. And if logistics works well, this have serious chance to be done again in a future host...
The main subject here is: IOC will change the traditions every single time they want or they agree with some host city. Rio is not the first one and will be not the last one, OTO, and you know that.