my thought process with 1 spar win being equal to 10 PKs is the fact that you can actually lose a spar, so it's not really as guaranteed a stat as when you run into a mob spamming your sword
IDC about the numbers though, and as far as hats go I don't really care for them either but I know the rest of the community does in a majority
also wouldn't really care if BKs weren't included in this since they've been boosted so hard and the current numbers make it hard to gauge what's worth rewarding