If something happened to Frodo

I hadn't thought of that.
I thought an Elf would have been the best Ringbearer (see my last post). But I had forgotten about Galadriel.
A Hobbit is the best Ringbearer. But I wouldn't trust Pippin with the Ring. Maybe Merry because, as you said, he seems stronger.
I still think Sam would have been a good Ringbearer, too.
But, really, I don't think anyone in Middle Earth could have actually destroyed the Ring. It was just a good thing Gollum went wild and fell. Except for Tom Bombadil. He probably would have gladly destroyed it.