I like having plants, it completely disguises the skippy and the plants love it. I just figure that the roots are more filter media, covered with good bio bugs. I think the plants help with cleaning the water too but then I don't like floating plants and underwater plants in the actual pond, they bunch up and go down the bottom drain and clog the pump. I have big stuff, taro and canna and some horsetails. The only real pond plants I ended up with in there are a PITA, I don't know the name but they are long jointed stems that snake around with small leaves, They grow everywhere, I'm always cutting them off and throwing them in the compost. Anywhere the stem touches water a new plant grows, and they grow and grow and grow. I give the ones hanging over the side of the skippy a straight across haircut every couple weeks. I'll probably rip out as much as I can find before I leave this winter or they will eat the whole pond.
I've only cleaned out the skippy once and that was to fix a leak on the bottom drain. I do open that drain into my bananas occasionally until it runs clear. I guess if I had to clean it every year and shut it all down I'd look at it differently, I don't know how you guys do it. Under the plants, which are all bare root, I have light grills and under that, matala pads sandwiching a box of SpringFlo tape. Another light grill keeps it about 8" above the bottom.