Wejo,
have been reading this board/site relatively recently.
(I have been away on vacation for the clast couple of days so i've no idea what else is going on. Actually I even wanted to start a thread "what's been happening of notice? on vacation for a while... could be a feature for people who like letsrun but aren't fiendishly addicted... ANYWAY...)
Part of the board attraction is sifting through the trolling and finding the pearls. Sometimes, if you sift enough, the catch is quite plentiful.
But even a bad day of fishing can end-up being quite fun trolling wise.
The feeling is like the sort of back-and-forth during a group run. It's like people post here while their endorphines are still flowing. And agreed, sometimes the stuff written is borderline. The quality guys can always run ahead of the trolls if they feel like it. And you should still be able to figure out the really malicious types...
Still the best exercise is recognizing people not for their identity but for what they write. It's not that difficult to spot a fake, even a fake troll for that matter, and its great, damn great mind exercise... just the sort of corollary support activity a community of runners needs, to filter off post work-out excess endorphines...
Your board, i'll like it either way. How much can changing your board change you? Still if you moderate heavily with registration it will change. Your call.