Hello Ken,
I understand most of the inconsistency that exists in the current rules for card shortages in stud. A couple facts I'd like to clarify for those that are not that familiar with seven card stud. The dealer must always be aware of a hand playing out with a full table of players still remaining. I like to teach student dealers to count the number of players before burning and turning, especially on sixth or seventh street. In order to assure that there will be no shortage of cards on a particular street. There must be at least two more cards remaining in the deck stub, than players. Six players...eight cards. This, of course, will allow for a burn card and one remaining unused card. The old rules would tell us to never use the bottom card of the deck.
Local casinos are in favor of using a "community card" when it is obvious that the stub does not contain enough cards to complete a round of dealing. This will only apply on seventh street. The alternative, in certain situations, is to include the burn cards along with the short deck stub, when possible. This of course will take a little more time and that's probably the main reason why most casinos frown on it, and prefer a community card. It has been my experience that the shortage almost always happens when the early rounds are checked, or minimal action has occurred, thus the remaining players. There are other situations when a complete street is removed because of a premature deal, but that could be a subject for a later discussion.
I'm not sure what kind of a change you're looking for. Once a player receives a down card and the next player (through dealer error) has his rivercard exposed, it's usually impossible to ask the first player to turn his up.
The way I see it: On seventh street: If there are not enough cards to complete the deal by adding the "clean" burncards to the deck stub...use a community card.
As far as the mistake of the dealer, accidentally turning the first players rivercard up instead of down, well, I always thought that could use some work too. If the dealer is going to make a mistake on the rivercard, the first card off, after the burn, is when it will occur. I actually prefer offering an option to the player with the exposed card. I'd even prefer that when the first player accidently has his rivercard exposed. In other words; dealer burns and turns the one-seat's river card face-up (hopefully by mistake)...I'd prefer that he continue dealing the other players their rivercard down. I know that's not the rule, but that's what I'd prefer. Head to head adds to the complexities, as Ken mentioned.
I don't know if I'd be in favor of automatically declaring the player that received his downcard and it is intermingled with his other holecards, all-in. I'd prefer giving the option to the player or players with the exposed hand.
I don't know if I answered any of your question, but I thought I'd try to explain what I remember from those good old stud games, from years gone by.