New game engine, putting aside concerns of Epic exclusives and such, seems fine,
but changing the name, it's not to signify the game studio will focus on halo, 343's name is based on the franchise; "New name, new philosophy", it's trying to distract from the past trying to say "under new management", but in recent times companies have used this as smoke and mirrors, hiding that nothing has changed.
I'll believe new philosophy when a game comes out that isn't trying to be destiny or cod and doesn't have 50% of the game missing at launch because of mangled management that was fine shipping an incomplete game and never finishing it.