And it looks quite good to me so far.
The Release Notes list a ton of fixes.
There's a Light mode UI now.
And the Layout studio has a new "Object Captions" feature, which looks like it wull really improve my workflow

Wonder if this means there won't be much to report new at the Canva worldwide event next month?

You're absolutely right.
I get the impression that the 3.1 (or March 26) version is primarily a "stablisation" release addressing a significant (~200?) bug fixes, and in delivering them a number of improvements and additional features were able to be incorporated. Undoubtedly other developments and fixes are still being worked on. My experience of software development tells me that there is also a case for not delivering too many new things at one point, as that may generate more corrective action...

Or, as computer science theorists like to say, “For every error correction there is a probability p of generating lambda new errors.”

Like everything else we’ve been promised, I’ll believe it when I see it.