I’m sorry but I was in that thread and the A1 rating thing was anything but popular (no offense to those involved). The rating system of 1-5 star with Jam Charts is fine.

The main issue is, as you pointed out, abuse of the ratings system with some shady character (s) bombing reviews to alter scores. Others have shown this by monitoring review scores over time and there are clear spikes of 30+ reviews coming in all at once. Phish.net should require your phone number or a reCaptcha check to leave a review. Either solution would most likely fix the issue since its probably bots doing this or someone with 30 email addresses.

No need to reinvent the wheel in my humble opinion.