Originally I waited for quarantine reasons, but since he was happy I figured I'd let it be. He's never been depressed or seemed lonely, he's in great health, he's very active. The only thing is, he's a bit of a coward. If I try to introduce anything new to the cage, he will not go near that side (for months) until I finally remove the offending object. I can change out items that were in the cage when Brisbane was alive, and that's fine. The same applies for foods. Brisbane always tried things first, so I think that's why. But new things are a big no no.
Anyway, long ramble for this. I was wondering if getting him a friend would help him be braver (maybe he's not quite at ease?). I was thinking maybe a society would be easier to introduce, but I've heard you should only introduce birds when they're young? So is getting him a friend a good idea, or should I leave him alone since he's happy and healthy? If I get another finch, should I get a society or zebra? I have a spare cage so I could put the cages next to each other after the quarantine period to help them get used to each other. But I can't do chicks so it'll have to be a male (I'm hoping if I get a society I can catch one singing). My other concern is if I only get one society, before they go together it'll get lonely.

Sorry for the rambling questions,

Edit: I'm also hoping this was the right board to post this question too, I couldn't tell.