Dont cheap out on a $500 filler if youre determined to do it. That’s how you get those floods. Get a good one. You’ll still have gross bacteria laden water that isn’t fit for consumption. Might as well just glue on a cheap spray painted trim kit and don’t even plumb it, if you want a cheap decoration.

I personally wouldn't worry about matching, it isn't right next to the others anyway. it shouldn't be the focal point of the room.

I think Champagne bronze hardware could look dull with Kohler brushed brass which has a very gold tone, and so does the gold pendant.

I don't love it either, as I prefer a very light aqua color, but what are you going to do? I think your yard needs some other strong elements to balance out the bold blue of the pool. Maybe some ceramic planters in blue with pool friendly plants ( things like succulents, bromelia, etc that don't drop stuff all over the place) Here are my planters to give you an idea.. Mine are a beige color to go with my more muted look, but you could go bolder to complement the pool color. More like this ... Scatter 9 planters, in groups of 3, around the pool and patio. This one ties into the dark blue tile, which is closer to your pool color.