Furiosa is an acceptable addition for showing us expanded lore of the regions and characters that were introduced in Fury Road. I enjoyed it, it has its own tone that is very different from Fury Road. To me, Dementus is Chris Hemsworth's best acting performance/role to date. I'm not crazy about Marvel movies so I'm indifferent about him as Thor. I would've preferred to see Charlize reprise the role of Furiosa, but understandably so, she is too old now to portray the character in her origin story. Anya Taylor-Joy was just ok as Furiosa imo.
It'll indeed be a shame if The Wasteland doesn't happen because Furiosa didn't do well in theaters.