Let me start by saying I have never been a Sq/DO, but the best DOs I had all did the same thing. They each spent a day or so with every Flt/CC and their NCOICs so that they could best understand the full capabilities and limitations of each flight. They would listen to where we were finding success and encouraged us to push the envelope there. They would listen to where were struggling, but instead of trying to be a "fixer" they were a "supporter." They did not try to micromanage us until we had the problem moving in the right direction, but rather, they gave us additional tools that we might not have had direct access to or would help provide the muscle when we ran into road blocks. As an example, there was a brief time where the AF had a rash of tractor-trailers that crashed through perimeter fencing. At my base, there was a chain link fence, but nothing that could stop a tractor-trailer from ramming it and ending up on the runway. The Wg/CC wanted to install a secondary vehicle barrier fence at the end of the runway. Without going into too much detail, the area where he wanted the fence and its relative location to the runway was a violation of multiple rules from the FAA and big AF that governed aircrew/aircraft safety in relation to security. After I briefed all this to the Wg/CC, he still wanted the fence and wasn't taking no from me. I explained the problem to my DO, gave him all the rules, built maps, etc and he went to the Wg/CC and told him it was not feasible which stopped the idea. I guess no comes better from a Lt Col than it does from a Capt.
The other thing that made them successful, at least in my eyes, was being in lockstep with the Sq/CC's guidance and intent. It was always frustrating to me to have the CC telling me one thing and the DO another, but the ones that were on the same page with the boss were the best. I never had to question what direction my flight needed to go in or what our expectations were when I was getting the same ideas from the both of them.
Also, set clear expectations for flt/ccs and shops. One of the most refreshing things I've heard was "you don't have to come to me for these things, I trust you to do the right thing."--that only works well when people get their expectations and scope of authority.