I keep my Bolt on 7, but it can do 9, that gets too small for my eyes. I have a hard time seeing any detailed text in any case. I tried bifocal cycling shades but found that the view wasn't where I needed it, and they were otherwise crappy glasses. Maybe I'll try different pair, but the Tufosi shades I bought to replace them are really nice. I guess I just have to remember the order the metrics are displayed since the numbers are big enough.
My old Cateye Astale 8 could do 8 metrics total, and you could only display 2 at a time and one had to be cadence or speed. Things have come a long way.