I think there are a lot of cool things in the Mawtribes book (Meatfist boys here we come), but also a lot of highly questionable decisions. There are rules in this book that I read and say "Who the hell thought this would be useful in any capacity?" Maneaters are still bad--having 12 wounds with a 5+ save was awful last edition and still worse in this one, and they're pointed like some kind of elite unit. The Tyrant still hits like a wet noodle and they took his awesome CA away...I don't know who in their design studio refuses to give Tyrants more/better attacks, but they can go to hell.
Also, why the hell are Ironguts 270 points?! Even the new Chaos Chosen, patently better versions of the Heavy Infantry archtype, are 240. I think we'll definitely be seeing some needed points drops in the future for Mawtribes.
I'm still looking forward to trying them out. I think it'll be very similar, but with even less models on the board and potentially higher damage output. We'll see if the changes were enough to get them out of the 40% bracket.