One thing that really doesn't make sense about this site is that I can submit more open offers than I can actually cover. So for example, if I have $1 of available cash, I can submit a $0.75 open buy offer on one market and a $0.60 open buy offer on another market and my "available cash" is not affected... unless one of these offers is matched. Any time an order is submitted, the same amount of available cash should be reserved for that offer, otherwise this can result in negative-balance situations (e.g. if the previously mentioned set of orders were both able to clear somehow, my cash balance would be -$0.35).
Disagree. You don't know that an open offer will ever be met. In your example, the sight lets you make 2 offers and the one that hits, hits. This is much better. Otherwise, you'd have to chose only one, the one that might never be hit.
I also think it would be nice if PredictIt was able to somehow remember previous offers. Example: I put an offer in for 100 shares on Contract A. Then I buy something else, and so it cancels that offer. Then I sell something, freeing up some funds, but my offer on Contract A has to be made again. It seems like this could be fixed by just keeping my previous 100 shares as like a ghost offer, that only I can see, that reappears when I have the funds to cover it.
mary has it right. the order should still exist, but not be public or executable