It'd be great if we could have the option to only plot to the chart limit within (say) half the chart size of the variable. I believe some of the old (d) charts did this. If you're observing a 16th mag variable, you want nearby comp and field stars of course, but you don't necessarily want the entire chart populated with all stars down to the chart limit! Maybe the 'outer' stars could only go down to 2 mags above the chart limit?
So, for a (d) chart to 14.5m and of a 1 degree field, all stars to 14.5m would be plotted within 15' radius of the var, but outside that area, only stars to 12.5m would appear.