It feels kind of funny to think that the thing I'm seeing the most from Soul Caliber VI is the character creation. I wouldn't expect something like that to be so popular, but I suppose people have just been
that creative
.
That's unsurprising. In Soulcalibur 3, the CaS was regarded as one of the best characters creators during it's time. When Soulcalibur IV came out, lots of people were at first excited about the CaS, but people then saw how very limited and limiting, ESPECIALLY with the fact that parts altered your HP and ATK. Combined with the fact that CaS no longer had their own movesets technically and the weapon choices were stuck to playable characters only and even then, it didn't include guests or Algol, people weren't happy.
Soulcalibur V fixed alot of issues with SCIV's CaS and made it surprisingly versatile in creating characters. Also, while it still mostly kept weapons limited to the player characters, the choice of weapons were expanded upon, like Siegfried's style having a Katana, Mitsurugi's style having European swords, Xiba's style having a couple spears, etc. It also did add in a exclusive weapon for Created characters, being Devil Jin's moveset. Combined with it's surprising amount of depth to customizing, it had the potential to rival Soulcalibur III's CaS.
It wasn't without flaws though.
-The first problem was that while the items weren't as limited as Soulcalibur IV's list, some outfits did restrict customizing alot though, especially the main characters' outfits. Compared to SCIV's 2P outfits which could go with alot of options, there was almost little to no point in using the outfits for original characters.
-It's 2nd problem was that much like Soulcalibur V to VI, much of the items from Soulcalibur IV didn't make it over to V, which saddened alot of people who wanted to use their previous CaS outfits from IV. It also had the issue of not making 2P outfits from the main characters as available options in the base game. For DLC, it did add playable characters outfits eventually, but as mentioned, a majority of them were very limiting that there was next to no point of using them for original characters except for the ones that weren't limiting.
-The 3rd and biggest issue was that there was nothing for people to really use their CaS characters for. Soulcalibur III had Chronicles of the Sword and, while CaS didn't have it's own mode, CaS did have their own Arcade "story" for their characters. In Soulcalibur V, there was no mode for people to really use their original characters. They could use them in Arcade mode, Quickplay mode, online and whatnot alongside the main characters, but there wasn't a mode just for CaS characters alone. Nothing to really "show off" their character.
So really, Soulcalibur VI's CaS is nothing short from Soulcalibur V. While it does solve the 3rd big problem with Libra of Souls, allowing people to use their character for their own mode like Chronicles of the Sword and it does make the main characters' outfits available for the created characters, it still suffers the 2nd problem of removing alot of stuff from the previous game to the next game. 257 items from Soulcalibur V are not back in Soulcalibur VI and it seems like there is alot less stuff compared to the previous games.
It does add "races" to the game, which are basically permanent "cosmetics" added to the characters, like the Skeleton was a "body part" in Soulcalibur V, but now is a race to allow for some easier customizing, I assume. The Good Lost Soul race adds the Angel Wings back part from the previous game to the character. In short terms, some of the races are just modified human characters that add a permanent part from the previous game to the character.
Anyway, Soulcalibur VI's Create a character issue seems to be that there aren't alot of parts to use. As mentioned, 257 items from V did not return. Also, once again, there's no unique weapon for CaS, although it does make all playable characters' movesets, including the guest's moveset, available for original characters. So basically, while Soulcalibur VI fixed some issues with the CaS, most notably the mode for CaS characters, Soulcalibur VI's CaS still leaves parts to be desired. In terms of available items, Soulcalibur III remains the king in it's choices of parts. In terms of customization options though, Soulcalibur V and VI compete with III.
That being said, I would not be surprised if the reason for no unique moveset for CaS is due to the fact that created characters are frowned upon in the competitive scene in general, due to factors like changable height which in turn can give a character more range/damage/etc. Like, despite the fact that in Soulcalibur V, there is a "default" height for characters for the weapon styles, including for Devil Jin, because there is no default Devil Jin character for people to choose, Devil Jin is not used in tournaments.