Sounds OK, maybe 25mins at 70-80% Max HR every other day.
I do 3 cardio's a week:
40 min = 10mins on 4 different machines - exhausted on each 'set'
25mins then machine thigh workout - I'm rehabing my knees!
25mins then Abs & Calves (weak body parts that I'm bringing up)
Also 6 mins cardio begining and end of each workout as warm-up/down.