RE Rasmussen vs Hughes - I wouldn't make the trade.
1) Comparing who is better when they are totally different players in style, physique, skillset and position seems like a futile task unless on is a totally different tier of player to the other.
2) Rasmussen has the potential to offer something to my mind more unique. Hughes undoubtedly has special skill and skating, but if Ras can develop more strength (as seems very likely given his size) and a bit more motor (more of a question mark), he could become the best net front guy in the league, and a very useful guy in the corners, on the boards and in the forecheck. I think hughes' style of d-man is increasingly common in junior and breaking into the league, so given our likely poor NHL performance next year as well, I give us a greater chance of picking up a hughes style guy than a Rasmussen style guy. Rasmussen is stylistically a bit of a throwback, and as long as there aren't too many of them on the roster, it could be useful in complement to others. Also, I;ve been sick of seeing us get dominated by middle line 6"4+ centers so much over the last decade, from Staal's to Bjugstad, and the potential of someone who matches up well against that sort of player, who is already defensively responsible is something I'm keen on.
3) Hughes is such a boom/bust player at the NHL level. We KNOW Rasmussen will be a useful NHL-er with a clearly defined skillset. Hughes may turn into a midget Erik Karlsson. But he may also be unable to cope defensively with the size mismatch as an NHL dman - what I've seen of him does leave question marks in this direction.
Of course, if we draft the younger hughes, I might answer differently, because one would assume they have a good understanding!