Destine paralele

For me, this book is the definition of lost potential. The idea of the story is really interesting but is poorly written and the characters are not just weakly developed but they don't even seem to have a personality of their own.
The narration of the actions from the 1400's failed to give me the medieval vibe as I felt like the characters could have been from any other era and it wouldn't have made any difference.
The climax was too short and seemed nonsensical. If all it took was for Roger to lead Melissa to his remains for the problem to be solved, why did he wait so long to do so? Why didn't he led her from the beginning? And why did he wait 600 years to do so?
A thing I liked is the satisfying ending for Roger and Sibell who finally reunited after so long.