Yes, could be... althought I don't think so to be honest... GE 5 is simply too high boost... if I wish to win all battles (yes I do!), I need more boost for my defendingg army than I ever managed to get for my attacking army! If I still wish to win till end of GE L4 and at the same time do GE L5 fighting? I need a LOT more place for my city.
And to be crystal clear : I do not expect to be aible to win NOW all of GE L5 battles ... it may stay as a new "goal" to get there over longer time.
Knowing this : just only aible to play a small part of GE L5 needs to be rewarding enough to play it, otherwise it give not the "fever" to get valuable pieces !
Yes, some players already found a way to beat GE L5 :
I've read there're players who can currently win all 16 battles of GE L5, ust because they're in Progressive Era and get units of +5 Ages higher !! Yes, that way it's, of course, possible ! Hmm... not sure what to think about such situation, players with units of Ages above their current Age ... Cheating or not?
Inno has to re-do GE L5 (or the whole GE?) ...