Just wondering if anyone has done away with the cable tray and routed the cables overhead across the ceiling? I’m considering it myself, but I’m not sure if I’m missing some blindingly obvious barrier to this.
You mean besides the tangled mess of wires, strangulation hazard, and possible code violations? Remember that the spindle wire has high voltage on it - there’s a risk of that cable catching on something and breaking, pulling out of the connector, or abrading, and you’ve got a fire and/or electrocution hazard.
Is this fear mongering? Yes, but those are the blindingly obvious reasons 
In my case, I ran the wires in the cable chains and still have to replace some of them because I didn’t secure them well enough and they scraped on something they shouldn’t have (not Avid’s fault).
I worked on a lot of automated equipment (before I retired), and its hard enough to get a long life out of wires that are constantly moving like in pick and place machines and CNC’s. I can almost guarantee you that you will get less life out of the cables if they are hanging from the ceiling due to the extra strain and it being concentrated in one spot.
These are all good points. I hadn’t taken into account potential, fatiguing of the cables. I can’t help thinking, though, that there must be a solution for this. Given proper support I don’t instinctively see overhead cables being worse.
That said, this isn’t something I’d pursue without a confirmed functional (and safe) system. I’m happy dangling my extractor hose from a glorified rubber band, but I won’t mess about with electrics.