I think NR, Monsters and SK are all viable now at high ranks. No one deck from any of those factions can dominate the other two consistently, plus mirror matches also make for a toss up. They also each have a few strong archetypes. As an example, NR has reaver decks with both Foltest and Henslet, as well as Radovid control.
It is ST and NG that are hurting now. I hope they both get buffed during the next patch. The ST farseer looks like a game changer for sure. I'm more skeptical about NG. Maybe they'll give Calveit back his old powers.