good timing to post this question! I just got back in town yesterday so I can help you out.
There's a 100 different ways to do a build and 1000 to do it wrong but we have helped out lots of folks who have had the same questions.
Drivers are dependent if you want dimmable or constant.
Dimmable with potentiometers or done with a controller like an apex or profilux.
Optics relates to tanks that are really deep or the height of the fixture over the water line. Most folks hang their fixture over 8" so typically they go with the Carclo Ripple wide optics.
Color combo is based on your personal taste, no one can tell you what kind of burger you like to eat. If you like it really blue then go for a 3blue to 1white ratio. Most folks go with a 2b to 1w ratio so we based our phoenix kits on those numerics, it looks like a phoenix 14k bulb

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I am looking at doing your size tank or a bit deeper for my next tank and there is two different ways you can do it but its dependent on your rockwork and budget. I am going to use the Phoenix kits as an example but you can use comparable quantity LED kits with different options. We just use them as the recommendation since they are the highest quality kits on the market.
(photos from here
LED My TANK! « « ReefLEDLights | LED Aquarium Lighting ReefLEDLights | LED Aquarium Lighting)
You can do
2 24"x8.46" heatsinks with a Phoenix 55 kit
Or you can do 3 18"x8.46" heatsinks running perpindicular to the front pane with less LEDs on each heatsink.
Hope this helps you out.
-Rick