D isn't actually their weak point at this moment, Gio is year older, but i think he is going to bounce back. They have lot of trust for Andersson and Välimäki to take big steps soon. Andersson has already, and he is going to play that PP1 surely, and they could always bring back Gustafsson, Brodie, or Hamonic. So I don't really get some of these trade proposals when people are pushing ADA to them and saying give us everything you have. ADA is god, Monahan + Hanifin or no deal. That is not going to happen. Its pretty obvious they wanna shake their core from front. That's why Gaudreau and Monahan are on the block.
Maybe ADA is interesting option for his age and RFA-status, but that is not necessity for the flames. So I think Buch is that piece, what they maybe are after.