This would be more impressive if it didn't so often happen that the ones with the best-sounding evidence so often turn out to be outright fraudulent.

Yes, that is a problem - if you're making up the claim, you can make up evidence to be as convincing as you want.

Yeah, they do indeed require evidence sufficient to convince the church that the person is in the afterlife. Unfortunately, it doesn't seem like the church needs terribly good evidence.

Considering that the Church already thinks that there is an afterlife, the burden of proof they require is almost certainly lower - possibly significantly lower - than the burden of proof that you would be looking for... it's just the potential source of evidence that came most immediately to mind at the time.