I forgot how much T7 improved from Vanilla to FR, if SC6 gets the same revision and treatment at that level in some future we may get something incredible to say the least.
Well, that's kind of a strange way to look at it, it seems to me: if I understand the release history of Tekken 7 correctly, the console/PC release was based off of the T7:FR release (itself an update of the first T7 arcade release), but the console version added new more new features and content than T7:FR, and said content was then re-released back into the arcades as T7:FR2. By comparison, Soul Calibur has started out on console and there's no reason to expect an arcade version at this juncture, since the franchise has not been a cabinet system series for some time. Any content that gets added to it they will just use the base game, without a re-release of the basic product, just iteratively using updates, precisely as they are using the season pass(es) and patches now.
I think even if they added entire new mechanics to the game, they would approach it that way; I think consumers in the present day would rebel if they were asked to buy an entire new version of the game unless that same version could not be achieved (with full compatibility between players) simply by updating their existing version: they would have no issues with a version that is essentially a sales bundle of existing content at some point, but dividing the player base into different versions of the game is not really viable, and they are going to allow people to buy the game however they want.
Even with Tekken 7, notice that the versions went arcade-->updated arcade version-->updated console version ported to console and then updated further-->arcade version equivalent to updated console version. Nobody cares if you release technically inconsistent versions on arcade because A) The end-user consumer/player isn't paying anything for the hardware, they are paying for use and that rate won't really change in most cases between versions, and B) it's local play, so there are no technical compatibility issues. Whatever happens with Soulcalibur will certainly happen through patching of the base experience, which is what has been happening with the game to date, in an iterative fashion--I wouldn't expect any huge re-releases until the very end of the game's lifecycle, and even then I think it will just be a comprehensive version of all the content released up until that time.
Although it occurs to me now that I've said all of that, that maybe you just meant "if SCVI improves as much between its original and final version as T7 did between the first release and FR, it will be a far superior product."