Rob- I still want to do conditioning twice a week at least, even if that is at the expense of maximum muscle growth. Do it after a lift and have 3 rest days? Or do it in the AM on lifting days?? Also you recommend less volume for growth?? It bears saying that the 5x15 is high volume/less intensity. Does that alter your opinion at all?
Based on your stated lifting experience you're likely to make significant gains regardless of the exercises you select, as long as you eat and rest adequately. My emphasis was on including more rest. I suggested the light cardio day as I feel conditioning is the activity that would make the smallest contribution to strength and hypertrophy, and light cardio can be active rest - it's not a great way to provoke adaptation. For scheduling, either option (after an upper body day or AM) could work. Try and see. I, and you, don't know how you'll respond until you give it a shot.
I do think lower volume, higher weight would be better for strength (your first goal) and hypertrophy (your second). If you'd said growth first, I would have suggested 3x10-12. I defer to the far more knowledgeable people here for exercise selection and hypertrophy - I can't really talk about that stuff. After my summer of training i'm several kilos lighter, my arms and legs are thinner, and I eat fat and carbs like they're going out of style. I do not train for appearance or size. However my resting heart rate is now in the low 50's, my blood pressure when last measured was 120/80 and my life is quite wonderful. Go figure.
If you take a three month view you could program strength for a month, growth for a month then endurance/cardio for a month, then repeat. You already appear to know training all three at once can reduce progress.