Ok, i personally love variety in mine. mix up the excercises and times. For example, run one day, sprint another, jumprope another , do sport specific stuff another, stairs,burpees another...
Mix up the times, ill do 30s max intensity with 30 seconds or a minute rest, or 1 minute on, 30s-1min off, or 2minutes on, 1 minute off.... or ill run for like 20 minutes with intermittant sprints thrown in
I usually do it like this, condition 3 days a week
day 1 ill go on the stair master for 20-25 minutes with alternating sprints on it
day 2 ill do 1-2 minute intervals of burpees
day 3 ill do punchout drills for 30s rds and kickout drills for 30s-1min rounds and then some jumprope sprints or burpees
then in class i do lots of sport specific burst training like 30sec fast kick drills or bag drills.