From what I have read pods will go through a return pump just fine. I have a refuge in my sump and I could honestly quit feeding by banggai with the amount of critters in the water column of the main tank! I'm sure many of them are coming up from the sump.
As for lighting, with 175W bulbs I would stick with 10K as they are a nice colour and usually provide more PAR output, plus with a lower power like a 175W you probably want as much output as you can get, all depending on what you keep. If you have the chance go look at some 175 bulbs on another setup or in the store before buying a particular model.
If it were my tank, i would ditch the close loop and go with the tunze streams. They move a ton of water, are extremely reliable, and use very little power. Plus less pipes and wholes in your tank, less to go wrong. The main complaint against them is their size, but when positioned right, you will hardly notice them, specially with all the corals to stare at
Sounds like you are doing some good planning though, should be a nice setup!