I know you guys up North tend to do things different, but here the norm is to build a platform for the equipment in the attic. We never had vibration problems. I think the wood dampens the viration a little. If vibration was a problem vibration isolaters would be used.
Its a 80% vs with a r/a chase you barely can here it in the living area.
There is a drain on the emergency pan you can't see it in the pictures. It's on the backside.
We form and pour the slabs ourselves. I don't like the plastic ones.