I agree. I would only add two short things.
First of all, the more BRICS expands—now, as of this year, it includes Egypt, Ethiopia, Iran and the UAE—the harder it will be to gain consensus.
The second thing is that between China and Russia, which are the two largest countries in BRICS, I think there's a fundamental difference in what the purpose of the organization is. Russia is trying to turn it explicitly into an anti-western organization. China and many of the other founding members, I think, are not on board with that vision, so there's some daylight between their positions there.