@k98kurz My intuition also initially led me to the idea of -2 to +2 scale with 0 as default. I unfortunately do not have my sources in order, but here are the conclusions I came to after further reading:
- A default mid position has some weird and unexpected consequences. You can get a system which rewards the most unknown candidate.
- Approval/score/rated systems by their nature create more positive elections with less smear. This was immediately observed in districts which switched from FPTP to Approval. When a voter rates two candidates independently in a 0-5 scale, they have the ability to punish both candidates which participate in dirty politics or reward both candidates who demonstrate bi-partisan cooperation. This is especially true in large fields of say 10-60 candidates.