Formula does not look bounded by a min/max value. Yes, the score worsens the more concentrated the votes are.

Some real examples:
* [Using all voting power towards one account](https://techcoderx.com/curation?user=themarkymark) (-2.78)
* [Using all voting power towards self](https://techcoderx.com/curation?user=buildawhale) (-7.72)
* [Only one 100% vote](https://techcoderx.com/curation?user=randomvlogs) (0.95)