I would say Carle if you need a good (but not superstar) offensive d. Prob 30-40 points this year, average 40-45 during career, career year 60 points. Same class as Timonen, Hamhuis, Kim Jonsson, Chara, Campbell, Teppo Numminen, Matt Schneider, Ballard, Whitney, Meszaros, etc
Webber will probably get 25-35 points this year, average 30-40 for his career, best year of 50.
Brassard will probably see limited ice time this year in the NHL and probably won't break out until his 3rd year. I see him as Marc Savard type player with similar potential. Average of 70-80 points with 90 at his peak.