I feel like the isometrics have definitly helped my progress. In about 3 months I have added 35 pounds to my bench and increased my vertical leap by 2.5". Certainly all of this is not directly attributable to isometrics, but I feel the prooper use of them definitly helped. It is kind of "newbie" gains in a way because all through high school I trained using basically just training all of the standard exercises 3x8 or 10 with no periodization or structure or anything. When I got to college my strength coach turned me on to T-Nation and helped me learn the WS4SB template, which I use now, with some alterations to include more dynamic training as well as so iso or eccentric emphasis.
Anyways, I think you are on the right track definitly. I would change it slightly though. On your isometric day I would add some assistance work because your total weekly volume is a little low. A few sets of pushups or another comperable low-moderate intensity exercise would work well. For best results I would even seperate the two workouts. Do the iso stuff in the morning and then in the afternoon evening bang out 3 sets of 20 pushups or something. Or do the iso stuff in the morning and the pushups at night or whatever. For the dynamic day, I think you definitly want to keep the heavy lifting out of there. Push presses are not a bad idea, provided that you keep them dynamic. Maybe throw in 8 sets of 2/3 at a weight that allows you to really "throw" the weight over your head rather than "press" it. I would keep the weighted chins out of it. It would be fine to do 3 sets of chins at whatever weight (or unweighted) as long as you don't approach failure. Remember, the goal of assistance exercises is only to add a little more volume to the workout, not to add more intensity. You shouldn't really feel beat down after a dynamic workout like you might after a high-volume or heavy workout.
What do you think of this?
A. 3 sets of 20 seconds Planche hold
B. 3 sets of 20 seconds Pike hold
C. 3 sets of 20 pushups
A. 8 x 2 Dynamic Bench
B. 5 x 2 Power Cleans
C. 8 x 2 Push Press (easy weight)
D. 3 sets of chins (3 reps "in the tank" on the last set)
To me that would look a lot like an "intensification" block. Alternate a block (3-4 weeks plus an unload week) of that with a block of higher volume and less intensity.