1. I'd be blocked by too many people since I'm so annoying. That would make me feel bad. I also agree with the above comment that you'd still see the replies, so blocking posts probably won't be as useful as you'd think.
2. PER would be really hard to figure out since it is pace-adjusted, and making that adjustment... I wouldn't even know where to begin. Efficiency is a really great stat in a box score, but over the course of a season it loses meaning since each game has different circumstances affecting efficiency. For example, a bench player on a dominant BB team might only see minutes in garbage time along side other scrubs when the other team is still playing its starters, which will make a bad player look even worse with efficiency, while players who are only playing in important games, but not in games that are tanked for enthusiasm/GS reasons, might have an artificially inflated efficiency since he's playing along his team's best players with good attitude. I think there might be other useful stats to think about, so I think you are thinking along the right lines. Perhaps what we really need is a convenient way to do our own statistical data analysis or to have a convenient way to download our game stats into a consolidated database. I there there might already be some manager-generated resources out there for doing these sorts of analyses, so if there are maybe it would be nice for somebody to reference a post to them here.
3. Giving any sort of bonus to a captain is opening up a whole Pandora's box to all sorts of evils, not to mention that it doesn't really make sense to do that. That being said, the only reason to think about having captains would be to add to the dressing offered to Supporters, sort of like uniform numbers but less interesting. It would probably be an fairly easy add on to the game, but it would still take time to design and implement and this sort of thing would likely be way down on the priority list. In short, not a terrible idea if it's only a decorative thing, but don't hold your breathe waiting for it (unless you have lungs the size of Texas).
Thanks for generating some thoughtful discussion, keep the ideas coming!
Don't ask what sort of Chunks they are, you probably don't want to know. Blowing Chunks since Season 4!