I love the idea of our own lore and quest chains put together in ways that make sense for progression of levelling, exploring, and bosses. Leading harder and harder and offering routes for PVE gameplay. That's what will make high quality PVE, and I think that is more important than porting in bits of things from elsewhere.
That said, if certain iconic bosses/things/moments can easily be recreated from DEX, it would be a nice addition to content.