I have heard that 2p is interesting, but I feel that it is not the same game, and that it would be rather unexpected to encounter it in arena.
I don't have an opinion on card passing. Currently the majority of non-arena games don't enable it, but if that changes, or if there is a common outcry of arena players in this thread, then we can change the arena.
Players with opinions on card passing, please have your say here!