I trusted it a lot for a long time, and generally still do.
But as you mention the global settlement has me worried, so much that I'm afraid to even borrow any bitUSD anymore, because the bots will always go below margin call prices.
So to me it seems that borrowing should be a bit safer, and the global settlement shouldn't be allowed to be triggered by one account. Potentially an account that is harmful or maybe a badly programmed bot.
Bitshares is still my favourite in the cryptoworld, so I'm still looking forward to the future with it!