Agreed, if we have the chance to bring in a high talent player, such as Tuch, we need to go for it. The fact that he is both a goal scorer and power forward (both areas of need) make it all the better.
If Doughty makes the Olympic team, and Canada does well, it may result in the best time to move him (possibly to a team like Toronto for a playoff run). I'd be surprised if the Kings actually do so, however, as they likely want to hold on to at least one member of the SC winning team as long as possible (mainly for nostalgiae which leads to revenue).