First of all, kudos for trying to find new ways to fund open source. Those are needed.
This approach might work well for issues which require a lot of thought, but produce a simple fix and can be easily merged
This might go horribly wrong if outside contributors try to implement a major feature to a project which they don't have a good mental model for, produce a large patch that may get rejected by maintainers, or end up being rewritten-by-code-review, which would cost such maintainers more time than if they implemented the feature in the first place.
This approach might work well for issues which require a lot of thought, but produce a simple fix and can be easily merged
This might go horribly wrong if outside contributors try to implement a major feature to a project which they don't have a good mental model for, produce a large patch that may get rejected by maintainers, or end up being rewritten-by-code-review, which would cost such maintainers more time than if they implemented the feature in the first place.
It would be interesting to follow!