One thing Ive noticed almost instantaneously since changing my workout regime, is that
less exercises but with more sets/reps is definitely the way to go. It's been awhile since I've felt that good muscle tear feeling the day after a workout. Up until recently I was focusing four days a week to working triceps, biceps, chest and shoulders (back incorporated) with about 5-7 exercises for each muscle group. For example
Monday - Legs & Core
Tuesday - Triceps & Chest 6 different exercises, 3 sets and approx 10-15 reps for each exercise
Wednesday - Biceps & Shoulders (same as above)
Thursday- Rest
Friday - Triceps n Chest
Saturday - Biceps n Shoulders
Sunday - Rest (and hangover

)
While this routine has made obvious differences to my strength and appearance, I had definitely plateaued, despite increasing weights at regular intervals.
Starting this week, I've changed my regime so that it's much more intensive.
Monday is still legs, but for the upper body workouts I now just concentrate on 4-5 exercises per muscle group with minimum 4 sets on each. So now I just dedicate one day to biceps/shoulders and the same for triceps/chest. The forth day is dedicated to cardio & core.
I'm hurting more now after this first week then I have in some time, but it's that good pain so it's all worth it.