I was a fan of 'The Good Wife', the predecessor to 'The Good Fight', although I thought 'The Good Wife' spent too many episodes introducing characters, rather than the storyline.
'The Good Fight' has several characters from 'The Good Wife' and also references characters who didn't progress to 'The Good Fight'. In my opinion, it is mainly those characters who hold 'The Good Fight' together. Adrian and Barbara are 'new' characters who keep 'The Good Fight' interesting, but the show is mainly held together by Diane Lockhart, Marissa Gold, with the comedy being provided by the brilliant Elsbeth Tascioni.
The main problem with 'The Good Fight' is that the main newcomer, Maia Rindell is so wooden. It's hard to tell if her character is supposed to be like this (and if so, why?), or the acting. The casting for 'The Good Wife' was excellent, so it's unfortunate that the new actors don't bring anything unique to their roles (ie the roles could have been played by anybody).
It's worth watching, if only for those moments when characters from 'The Good Wife' are brought in for ad-hoc appearances.