Do you think that some of the reluctance to choose Q1 as a copy-text has to do with an editorial fear of considering that Shakespeare might not have had a "hand" in the changes? In your opinion, is that a legitimate concern, or is it standing in the way of better editorial decisions?
Along those same lines, the seven reasons you quote from Jowett's defense of Q1 seem to justify that version as more suitable for reading as well as performing. To what extent should one consider how a modern reader will encounter RIII and which play is more suitable for modern readership?