You're slowly getting there... As Ace says, I-Mast isn't actually designed for the Standard series, you are however correct in putting dedicated directors on there (at least if you don't have APAR).
I'm wondering if you could go down the route that the Spanish did with the Bazan class and combine the sensor mast with the funnel.
Finally, get rid of the portholes in the hull, they're superfluous in this day and age.