I do agree I also got bored with Phantom Forest.
But I don't think the 'easy combat' was the cause... more the convo/combat-ratio.
In the earlier areas there was quite some talking. If you fought, there were some optional dungeons to test your wits, another little side-quest, heck, almost all uniquely named enemies started a discussion with you before you fought.
Phantom? Straight-down combat pretty much. Very few NPCs to talk, those who did had very little to say. A lot of uniquely-named foes, none of them up for a chat though... it just makes combat... draining, if it's in such high quantities after each other, doesn't matter if easy or hard. Actually, it might even be more draining if each fight lasted much longer and was harder...
