In my experience with writing quadratic voting contracts in Solidity, the exponent of 2 is mandatory because there's no way to calculate an nth root in Solidity.

Writing that out though, I realize that the root could be calculated by the client and simply verified on chain.

One token, one vote is an exponent of 1, it should be up to the voters to decide the exponent used based on the issue in order to choose the degree money influences decision making.