It became very distracting to me. The film keeps centering around Count Cagliostro, and no one mentions that Lupin III has already faced the count in the film "Castle of Cagliostro". Thanks to Miyazaki, it is Lupin's most famous adventure, but they never do anything with that history.
I guess they realized that this movie already has way too much going on. Lupin gets married, they steal the crown jewels, the necklace of Marie Antoinette, MI6 gets involved, Jigen gets tortured and on top of everything Zenigata is still chasing after Lupin. That isn't even scratching the surface of all the explosions, betrayals and Mission: Impossible masks.
It is strange how much goes on in this movie, considering they spend the first 20 minutes on the same train chase.
Don't misunderstand me, there is a lot of good stuff in this Lupin adventure, mainly because there is just a whole bunch of stuff in this film.