I think it's good that you do something to occupy you while you work out, listening to the radio.
I think that perhaps eating and then instantly working out maybe isn't the best idea. Perhaps eat and then work out about 30 minutes later? When I used to go to the gym regularly at university, I would wake up, eat a bowl of oats, then walk to the gym straight away, but the gym was like 20 minutes walk. So that worked out pretty good, I usually had enough energy.
I don't know if there is an optimum time to spend working out. I often hear that it should be between 45-60 minutes. I normally hear that it shouldn't be more than 60. But a shorter workout is still valuable.
What I mean about goals, is that it's good to have a particular thing you're aiming for, either overall, or per exercise. When I am doing the exercise bike at the gym, I often feel like stopping because it's just boring, but then I remind myself 'damn it, you need to do this to lose weight'. And that kind of refuels me for a bit. Same thing happens if I am tired sometimes, I might have got to 6 reps on something, and I feel tired, but then I kind of kick myself up the arse and say 'You can get more, you just want a break' and I get a couple more. If I had no goals, then I'd see no need to push myself a little harder, so I think the long-term goals are good.
The other type of goal is like aiming for a particular rep count or weight to lift, keeping track of how much you've done. Say you do, I dunno, 50 squats in a set or something. I think it's a really good thing to make a note of that, and then next time you come to do squats, try to beat that. It stretches your limits which is always good, but it also provides motivation, because you'll be thinking 'okay I feel tired, but I know I can do more than this'. Even if you then fail and stop at 35 or something, you can wait and then do another 15 to make up, and then try again next time etc. It can motivate you to stay consistent.
splitting the body up like you're doing sounds good to me