Our problems on D are not so much from teams carrying the puck in, but when they dump it in. Outside of OEL, we don't have anyone that can get to the puck quickly and make a smart, split second decision. This is where Yandle would help us. Once the other team has control of the puck in our zone, I agree, Yandle is not the best. He has a tough time moving guys in front of the net, and can't out muscle guys in the corner.
Right now, Grossman is tough in front of the net but too slow in the corners. Z is solid positionally, but too slow. Murphy/Stone skate well enough but don't make a great first pass/decision. Dahlbeck is still young but can improve. I also think Smiths ability to play the puck is hurting us now that he is out. When he is in, we can play tougher at the blue line, force a dump, and let Smith get the puck.
I think Yandle would also help our PP a ton. We were a top 5-10 PP early last year, and are like 25th now, and that doesn't include all the shorties. Think of our PP with Yandle, we might be one of the best in the NHL. Signing Yandle should be a no brainer for DM/Tip. They will know exactly what they are getting and how he will fit in, if they want him. If they don't think he fits, they won't pursue him.
While I had rather have a top pairing RHD, I think signing Yandle will be much easier. A guy like Buf will cost a fortune and any other top pairing RHD will cost us a fortune in assets to acquire, if one is even available. Every team in the NHL except for a few, are looking for and will be bidding for that RHD.