Ever since I found out how sims get their One True Hobby, I've hated it. The way it's done basically means that all of your sims of one particular hobby will have similar personalities. That makes sense for some hobbies - sims who are into Fitness or Sports should probably also be active, for instance. But why, for example, do Arts & Crafts sims have to be nice? Why do Nature sims have to be playful? A lot of the criteria EA came up with just seems really arbitrary to me.
So I started randomising my sims' OTHs at birth. I was satisfied with that for a while, but after I had been using Starr's careers criteria for a while (which is partly based on interests), I thought I might try tying interests and hobbies together. This was a good while ago now but it's only recently that I decided to fine tune my system.
I'm going to start by showing which interests I assign to which hobbies. Then I'll show you a couple of examples of exactly what I do with that information to decide on hobbies for my sims, using a couple of Sullivan babies as guinea pigs. Babies are sort of blank slates anyway and I'm not yet wedded to the idea of any one particular hobby for them.
Anyway, so on with the interests!