Yes, they will definitely have problems with the plot. As I already wrote, the original Heroes universe looked like this according to Cannegham's ideas: here. And now, it is unlikely that they will be able to return to a global concept. Even NWC itself started experimenting with the Chronicles of Heroes, losing the linearity of storytelling, and Nival, which didn't know about this, is unlikely to come up with anything without connecting John Van Caneghem to the project.
Here, Murphy's eternal laws are repeated. Everything good gets spoiled in sequels. Well, as for the plot... :confused: (sadly hiding in the shadows)
Added after 10 minutes
Regarding assembled artifacts, I was disappointed not to find them in the fifth game. Although, considering the many identical names in the artifacts, (I really hope) they will appear soon. Here.