I don't have a BowFlex so I'm not sure what kind of exercises you can do. I used to find myself plateauing as well in the past. I went to a trainer and now I change my routine every 4-6 weeks.
One thing I notice that your missing from your current routine beside calves, is hamstrings. Also your deltoid muscles have three heads. By only doing shoulder presses you are only working the middle head (unsure of correct scientific term).
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