Not to be mean... but this is an odd post, considering the recent releases...
Advanced Tactics = Hex based
Guns of August = Hex based
Commander: Europe at War = Hex Based
John Tiller's Campaign Series = Hex Based
So, how can they RETURN to hex based games, when they are already producing MANY excellent hex-based games already.
Now, to the OP, I agree with RH and KG Erwin. Zone-based games have their place and can be much more fun that hex-based games. Sure, if you want lower level, more detailed and micromanaged operations, then hex based is the way to go. But if you want grand strategy, with diplomacy, research, economy, and political simulation, then zone-based can be very helpful to take the level of perspective higher. There are exceptions, GoA, AT and C:EaW are all hex based grand strategy, so it can be done effectively both ways. Different types of games, different types of play.
I do get a little frustrated with people saying "Stick with one type of game mechanic/map time/RTS vs TBS and only make those types of games!" This is short-sighted, a bit selfish, and close-minded. Why not have a wide variety of game-types and game mechanics? Would you not get bored if literally every game was a TOAW clone? Or even more to the point, since TOAW can be so open-ended, perhaps they should just make scenario packs for TOAW and forget new games? I'm all for variety. Nothing beats learning a new style and getting a new gaming experience.
"Neca eos omnes. Deus suos agnoscet!"
(Kill them all. God will know his own.)
-- Arnaud-Armaury, the Albigensian Crusade