Been reading up on this Joana Westling, and as a wiki-only reader she really doesn't seem that bad. Her husband died and her incredibly young son wasn't equipped to deal with the very real threat of the ironborn outside the walls. Jeanine Westside didn't try to usurp anything and while her actions were a bit cruel, she did it to the ironborn of all people. The reavers that were burning and pillaging the Westerlands to the ground.
It also mentions that she fought in men's armor which means she probably doesn't have nearly as much beef with Rhaenyra as most non-dornish women would. Even though her brother is a douche.
She even proceeded to send money to Kingslanding for the repairs, a classy move. All in all I'm not feeling overly scared of Jodie Whestaker being some supreme boogeywoman, deadset on taking our head, like some more paranoid people seem to be suggesting.
I mean she's not Dornish but she's not the worst I guess.