At full power, you are going to grow algae not plants without CO2 in this arrangement.
Your array will have enough spread, no need to add any more LEDs unless for the purpose fuller spectrum.
The color combo you will have is closer to reef settings than planted tank, are you sure you want that. Too much blue makes your planted tank looks weird.
I can hook you up with dimmable drivers for this kind of pico setups which I know, for fact, you will have a hard time finding them in the net yourself.
Parts you will need for something like what you want and I think will be more proper are as follows:
1 3x3W dimmable driver for 3 cool white
1 3x3W dimmable driver for 3 royal blue
1 power for both driver on a timer
(you can get one more timer to separate the blue and white turning on/off time)
2 moonlight modules
1 power supply for the moonlight on a timer
2 RS Bar fixture heatsink with splash guard
1 large DIY type heatsink at 4.25 inch depth, and length across your tank(you will have to device a splash guard yourself)
I can hook you up with all the parts if you cannot find them on your own.