Gotta say, not really gonna miss Juliette. She was a non-character for much of her run on the show with the "turning evil" bit the only time she really got developed.
What made it worse IMO was that Juliette went from kind of meh but nice enough, to an excruciating amnesia plot, to being legitimately cool as a supporting element of Team Grimm - the whole "You need to be a Grimm again" thing especially was a great moment for her character IMO - and then directly into a horrible permanent derail.
There was that short window of time when Juliette became a Hexenbiest, and all the other primary and secondary characters became fully aware of everything that was going on. It looked like it was really going to be an effective Wessen-fighting ensemble...
Even before that though - albeit before Wu found out the truth as well - you had a good crew.
And one element that I never liked much was the whole Woge thing, the way all these species of inhuman creature go around hidden in human form 95% of the time and only briefly show their true faces when provoked. That just screams "We don't have a big budget so we're gonna cheat and have our monsters look human most of the time." And the CGI Woge effects have never looked very good.
The "Game Face" is just an artifact of having David Greenwalt as a co-creator if you ask me, and just one of a number of spiritual connections to the Buffyverse.