Okay, KT, first go read my introduction and the full history and current state of affairs will become clearer. Up till about 6 months ago I was pre-press, reprography (b&w), and aerial photography (b&w). One photographer came to my shop and asked if I would take on he and his group of photo friends, stay analog, and bring in color. Hence here I am.
Answer your questions:
1. I am capable of handling ra4,r3,c41,e6 BUT only RA4 or E6 for higher volume. Hence I keep the C41 and E6 to in house use only. Furthermore I am testing an alternate solution so that I will never have to use either C41 or E6 in house. It would be imminently easier to use only RA4 or R3.
2. I designed and had built some special tanks which are neither fully hand nor fully machine. A little of both. My brain has to be present and accounted for while processing, ie I am in complete control, so I guess that would put it in the "by hand" category.
3. Sorry, won't answer that except to say that nothing is between the negative and the paper/film except the lens and the copyboard glass. In extreme enlargements, I have designed and had constructed an overlay for the glass frame, so that the paper/film adheres to the front removing the glass from the equation also.
4. For color right now the finished product is always a positive and in finished display readiness, so the customer decides; after I have evaluated using concepts like color correctness, saturation, contrast. If possible (not over 36") I scan it, as I find scanning often reveals "hidden" flaws and weaknesses. Of course this is not appropriate to check color correctness, but it does catch mishandled lighting, inconsistency in whites/blacks throughout the print, etc.
My refusal to answer #3 is adamant, if it were a simple solution you wouldn't be so annoyed that I won't answer, because you would have figured it out. Since neither you nor anyone so far has figured it out, I feel it must be a unique solution and am trying to see about a patent. If and once that happens I will be happy to expound.