Gallius Rax was probably meant to be the ersatz Thrawn rather than her. She doesn't have his tactical acumen or cultivated mannerisms and reminds me more of a hodgepodge of various one-off moffs and warlords in the New Republic Era EU stuff.
She's unquestionably a token, but the archetypal Imperial officer didn't have much of a proud and noble legacy to uphold. There's a difference between how the villains were actually portrayed most of the time and how "Empire Did Nothing Wrong" guys roleplay.
>>1863
Pictures I don't know, but she gets shown up and shaken in both A New Dawn and that short story where they shoe-horned in Vader for marketing power. I also don't know where you get the idea that Vader's cringing in front of her. There's nothing in his body language that suggests servility; he's a 6'6" easy looking down on a much shorter woman.
She's not a very good character, which is to be expected when Cuck Wingding gets creative control of anything, but I don't think she's especially bad either.