Just in case you don't know, the RB67 is much larger and heavier than the Bronicas - in the order of x2. If you are thinking along those lines, you may want to handle one of those before making up your mind. 6x7 is a nice format though.
I have an SQA and find much as you did that the waist level finder means I do not really need my reading glasses. Somewhat surprisingly, I do not need them with the magnifying lens flipped up although it is the standard lens and not one of the different diopter replacements you can buy.
If you do go MF you will not regret it as the quality improvement those large negatives give over 35mm is very noticeable. Of course, once down that slippery slope it's only a matter of time before the siren call of LF beckons...