I came up with almost the same activity but didn't think of having different groups decide the dimensions. Some random stuff:
Use stack ranking. Avoids "everything is a priority" and related mistakes.
Effort and impact both have a long tail distribution, something like power law. It's probably power law because it's easy to be off by an order of magnitude. "Impact" is easier to get wrong because it's going to the high end. Don't think most impactful and second most impactful have a similar impact because they're close in rank. It's easy for #1 to be 10-100x #2.
Use stack ranking. Avoids "everything is a priority" and related mistakes.
Effort and impact both have a long tail distribution, something like power law. It's probably power law because it's easy to be off by an order of magnitude. "Impact" is easier to get wrong because it's going to the high end. Don't think most impactful and second most impactful have a similar impact because they're close in rank. It's easy for #1 to be 10-100x #2.