Nice idea! One thing I've found is that direction also makes a difference. Sometimes one way has a better price than the other, even if both use the same fare class.
One other thing I came across on Facebook is that apparently Aegean is experimenting with 'Business class light' - allowing the Business class cabin, but not having things like flexibility and checked luggage. I don't think its yet clear what that means for mileage earning, however it may end up being a cheaper way for a mileage run.
Edit: Different mileage amounts for both types. Even though both in this example book into D-fare.
Full overview of differences:
https://upload.xandrios.net/16551541...2023.02.21.png
Mileage earning. Business basic gets 220%, regular business 250%:
https://en.aegeanair.com/milesandbon...rlines/aegean/