Upgrades to Sota Cosmos IV

Yes I have the Eclipse package. The improvements in sound are indirect and have to do with speed consistency. Older motors you can adjust the speed with a strobe. If you put the strobe disc on top a record with the speed set you will see the speed drift when you put the stylus down and the drift changes across the record thus pitch changes just a little depending on how much resistance the stylus is seeing. I also use a sweep arm which adds a little more friction. With the new motor the speed stays absolutely consistent regardless of pretty much anything. Thus pitch remains constant. Does it sound better. I think so but I can not tell you if the improvement is not psychological. It may seem strange to say but the music feels better. 
I prefer your Alphson as long as the bearings are snug. There should be no play. Any click and the preload will need adjustment. I do think you  would attain more of an increase in sound quality with a new cartridge but as I said that will cost you a lot more. I would do the motor first as it will out live many cartridges. But when you are up to it the best value in an inexpensive Ortofon cartridge is the Quintet Black S. As far as state of the art I can not recommend the Windfeld Ti highly enough. It runs with cartridges 3 times the price and out tracks most of them! It could be the last cartridge you ever buy. Just get it retipped by Ortofon. Your Alphson is perfect for it. You could also use any Clearaudio or Lyra cartridge. 

Yes Alan, all the old controls are bypassed. You can get the manual on SOTA's web site.

I have a Cosmos MK6, its a fine table. The mag lev bearing is top notch. The combination of it and the Total Eclipse motor/controller results in a noise floor floor that is way down there, and the focus of instruments along with timing is top shelf. I don't know which version of the Cosmos you have, but the IV is supposed to have the same vacuum system as the current one. 

I don't think you can go wrong upgrading your Sota. Cartridges come and go, but the improvements you are making to the Cosmos will outlast what you spend on it versus what you spend on the cartridge. 

Do any of you know whether the maglev bearing would have any effect in reducing groove noise or other record noise? Or does it only reduce low frequency "rumble" of the bearing? I currently have an old star sapphire vacuum but am thinking of buying a later model and having the maglev installed.

My hope is to reduce noise and maybe increase bass defition and or dynamics.  I would hate to drop net $3k on a used table and upgrade and find it sounds not much better than what I have now.
Thanks!