125# bench as max. Trust me, you do not need to worry too much about being disproportionate. I'm sure you can hardly fit through doorways with that type of strength. It takes years to build big arms, just keep lifting your body parts equally and you will be fine (no need to worry about disproportion). Here is the routine I have fallen into now that I am older, have kids and have less time to work out:
Two times per week upper body:
3 circuits : Bench, Lat Pull Downs (or pull ups), triceps press, dumbbell curls, crunches (you can do the whole circuit without really resting as you are working complementary muscle groups, just get water / rest a minute at the end of each circuit).
3 circuits : Dumbell fly (or incline press), Seated Row, triceps extensions, preacher curls, incline situps with medicine ball
You should be able to do the whole routine in under 30 minutes.
Two times per week lower body and core:
3 circuits: Walking lunges with dumbells or kettlebells, Alternating leg crunches, Reverse crunches
3 circuits: Clean and Jerk, Leg Lifts, Kick Backs
3 circuits: Leg Extensions, Leg Curls, Side Crunches, Superman/Banana
Again, you should be able to get through the whole workout in under 30 minutes
As far as reps are concerned, more is better, typically the sweet spot is working with a weight you can handle for 8-12 reps. Core exercise closer to 30-50 reps.