Attila: Seems to be a slow trend to go back to full body workouts, don't know why. Full body is productive if the exercises & sets are held in check. Full body is best suited for brief and to the point workouts, with focus on compound movements. Four to 6 exercises usually.
Twenty five sets (if not spending too much time on warmups..and in my view cooling down or finishing sets are never needed) should not make overwhelming demands on your body, but you might consider twice a week full body workouts rather that the three being done now. Lot's of guy's find this well suited for progressive gains as they get older. That is a lot of cardio included in your workout week. Any dire need for such extreme extra work I wonder? Body fat can be adjusted by simple diet controls. Would suggest interval training rather than the normal too long and too many cardio sessions a week.
If going back to a split, than might consider something like this:
Mon...upper body
Wed...lower body
Fri...upper body
Starting the following Monday:
Mon...lower body
Wed...upper body
Fri...lower body
Alternate again the next Monday. Work the abs, if you wish, on either lower or upper body days. Good Luck.