This is an interesting question. I also think the answers would vary significantly in response to the "how many are committed vs. zealous". In the congregation that we attend (sometimes) we have no elders who pioneer. We do have one elder that I would say is completely committed. I admire his honesty and example. He conducts several studies and helps those individuals in need. In my opinion, he does a Christlike work.
The remaining elders are pretty decent guys, but far from committed or zealous. One has burned himself out. One has been divorced a few times and is not really effective. Another seems very militaristic in his approach and is an outlier (few associate with him). The really good elders have resigned their positions. The remaining elders are family men who are reaping the consequences of following the WTBTS advice to shun education and it seems every ounce of their energy is spent taking care of their families.
The reason I focus on the elders is that the congregations seem to mirror the "norms" set by the elder body. All the Watchtower articles, talks, assemblies and visit from the CO and DO can never even come close to the example of the elders. So likewise the congregation that we attend has a couple of folks who are committed and even zealous and a bunch enjoying the ride. The remainder knows it is intellectual dishonest to be a Witness, but choose not to dwell on it.
Zarco