I really like your idea of raised spawning beds TJ. I would wonder if the SMB will find them disturbing sitting higher that the rest of the area. I certainly would have tried this idea had I known.
Someone recently also posted a tip on cleaning spawning beds. He used the discharge end of a trash pump to blow off the sediment. Sorry I can't remember who said it.
Combination of all these ideas seems like a good way to go.
Thanks Fish - I was worried about the elevated beds too, so I added as much additional cobble and pvc I could to try and make the elevation more gradual and less invasive or artificial. At full pool the beds are sitting in depths of 36-60", and I noted that 3/5 were being utilized last year. When I drainged the pond last Fall after seining the SMB YOY I noticed very little silt had accumulated, but I did have a bunch of FA that developed throughout the year. Dried FA is easy to remove though, like peeling an orange, and it was good as new.