Kevan Miller born in 1987, played his first season at age 25 (playing 47 games in 13-14), he didn't play more than 50 games until last year, at age 28. Colin Miller played his first NHL season at age 23 (42 games in 15-16), still currently younger than Kevan Miller when Kevan made it to the NHL.
C. Miller is a potential top 4 defenseman. And while he may not make it there, he has the skill, and is young enough to warrant the risk. K. Miller and McQuaid are approaching 30, are bottom pair defensemen in their prime right now. Nothing wrong with them, but they are what they are. Good, yet replaceable skillsets that are ALWAYS available via UFA, trade/waivers each year.
Protecting bottom pair defensemen over a potential top 4 defenseman is awful asset management. Even if C. Miller isn't in the plans long term, he should have more value long term. Swap C. Miller for a similarly aged winger, if he's not part of the plan. But don't lose him for nothing, while protecting players that shouldn't really be above our #5 defensemen ever.
If this draft was a few years ago, this would literally be the defensive equivalent of protecting Chris Kelly or Greg Campbell in their prime over Ryan Spooner. Yea, Chris Kelly and Greg Campbell were better at that time, but it's absolutely bad asset management thinking they are the better option going forward.
Pure skillset wise, look at this list:
http://www.spotrac.com/nhl/free-agents/defenseman/ufa/. IF McQuaid or K. Miller are selected, there are a plethora of defensive defensemen available, that are likely available without breaking the bank or even giving up assets. Losing a 24 year old that while isn't there yet, but showing improvement, is really bad asset management. The kind of bad asset management I'd expect from our management, but maybe they'll prove me wrong.