Couple of thoughts, this is something I have thinking about as well. I have a 50 card sub that is sitting on my desk. I have been flopping back in forth on where to send these - SGC or CSG.
For PSA, let's be real nobody is catching up to them anytime soon and that's ok. SGC and CSG (even BGS) need to think about who wants to be in that strong number tow slot. PSA is still doing 1 million cards a month and their backlog has been cleared for what 3-4 months now. The "hidden" backlog of those waiting to submit might start to ebb though.
As far as my decision between SGC and CSG, this is how I see them now.
SGC - better graders, holder needs updating, tux looks great for vintage less so for chrome/prism, needs a registry, great service, auto grades don't look as good
CSG - great holders, registry is ok but getting better, took a step back with the changing grading standards, did improve label greatly, grades vintage poorly, upcharging for autos and thick cards is a turn off.
My two biggest fears with CSG and holding me back from going all in are the fact they grade vintage more like BVG than SGC/PSA, this means they won't be taken seriously in the long run for vintage, and the other mentioned - they will find their niche as the "cheap" grader (even if that perception is wrong in reality).
As mentioned, I would also like to see them jump into more non-sports - hopefully in the CSG holder, but I would guess they would go into a CGC holder. That would pull me away from CSG if that were to be the case. I don't want them to go down the Beckett route and have a rainbow of colors on their flips and services. I don't want to see a CVG case for example.