The way I’m going about it is to pwn each forum with a range of luck values, keeping tabs on what’s dropped from each place.

If there’s a specific file I want to narrow in on, because it’s been found to be good or just looks interesting then I have a fairly easy way set up (macro’d bumons on a spreadsheet) to record drop percentages at a range of luck values, figure out whether it’s best to have high, low or middling luck.