The soils that line my pond are pulverized dolomite, which is basically limestone. This has lead to a nutrient poor pond, resulting in some fairly clear water and an excellent swimming pond. When we haven't had runoff in a while, the water does take on that blue-green characteristic of hard/alkaline water and can see at least 8' down. We do get plant growth, thanks to curly-leafed pond weed, but isn't too bad after 10 years of pond age, we still haven't needed plant management.

Key points:
1. Crushed limestone lining may free up enough hardness/alkalinity in the water column to make phosphorous less effective, and water conditions less hospitable to some plants. Note the FA is a rarity in my pond. You probably need a fairly thick layer of materials of a variety of sizes so it doesn't get locked away under sediments easily.
2. Consider parts of the pond non-swimming areas to let transitional plants grow intentionally. Especially on sides where runoff enters the pond. It will slow water flow to reduce turbidity, and catch debris before it enters the swimming area. I have buffers of cattails and pond lilies on the upslope side from where all my runoff comes from. Both of these plants will capture excess nutrients from the bottom decaying materials and lock them up. They don't really pull from the water column directly.
3. Chara will come naturally, and makes an excellent "skunk bomb" for kids to throw at each other. It does grow very well in alkaline waters. Part of the reason I don't have much FA is chara out-competes it.
4. Alum treatments when limestone isn't doing the job entirely.
5. As suggested, you will want fish. No bluegills, they are jerks. I have yellow perch, black crappy, and walleye in my cold waters, and you don't see them swimming unless you stay very still. The one lone bluegill will track you down and bite you out of spite.
6. Keep pond construction as far away as possible from trees and anything else that would put nutrients in the pond.