a) To some, the "delta" triangular chord symbol signifies just a major triad, and you have to write "delta 7" to indicate a maj 7. To others, "delta" already means "maj 7". What's preferred for what, by iRB protocols?

b) If you have a repeat barline at the beginning of a section and one at the end, is there any customary understanding as to how many times you do this loop-- or are you basically stuck here, like the MTA rider " 'neath the streets of Boston"? And/or, is there any customary way of indicating how many times you do a certain iteration? (I tend to put a "x2" or "x4" etc below the end repeat.)

c) If, at least as far as chords are concerned, the 1st and 2nd endings have the same structure, do we really need to spell them out separately, per iRB protocols? Or would an indicator like "x2" do the trick and save the space?