Not even a stance, just more inputs instead of the boring mainstream ones. Like NiCO’s 6PPPP for example, it’s a really good string and is really mashable.
DOA doesn't need more "difficult" characters. There's already Phase-4, Raidou and even characters like Hayabusa, Brad Wong, Ayane, Helena, Christie etc. aren't exactly easy. However, I am all for more characters to have a bit more complexity to them than NiCO & Diego whom are way too simple in comparison, and thus get boring easily.
It was a major criticism I had with Momiji & Rachel too: their core gameplay was way too simple to be interesting in the long run, and applaud TN for removing them. (If they do return, their movesets will need to be overhauled to be more interesting).
Rig is the only "all-new" character in the post-Itagaki era that has thoroughly impressed me. The rest are a bit underwhelming at best or downright offensive at worst.