I don't like the 4-8 rep range idea. Either train for hypertrophy or train for strength but don't train for both. Hypertrophy is mostly in the 12-8 rep range and to a certain degree 6 reps, but nothing lower. When you want to break a plateau or to add strength do an exclusive strength/power routine and roate between the two.
Get rid of the slow tempo.
I gave some advice in your other thread on what you probably should do to find appropriate volume for YOU. You just can't assume that any volume will do is PERFECT long as its not at the extremes.
As for the excercise split not sure if i like that either for how you put back with chest etc.