I think a lot of the nerfs they made make sense. Did you *evar* use anything other than Biomancy in a Tournament? I hated the biomancy chart–I still do. Look at what Mephiston does every game...
Carnifexes were not terrible, they just lost their awesome to make room for Trygons.
However, gaining fleet makes Carnifexes terrifying again. That's fine by me.
Shrikes were always a unit that was just fun. Giving them fleet shifts them from being okay to in the really good category. Talk to any Shrike player for space marines: fleet + jump pack = awesome.