I ran 16 flat this year in cross and 16:08 on the lavern gibson course. I was doing around 40 miles a week all summer to my PR. I want to really improve and get good this spring....should i do two workouts of tempo or some type or lactic threshold aerobic improving runs a week? then a long run of 10-12? also what should my easy paces be? is this a possible goal? also core everyday and lifting. any advice or help please give to me! 60-70 miles this winter max miles?