I am quoting someone (but forgot long ago who said it) when I say "all analogies limp." It's true. Analogies are illustrations to help us understand something, but all are imperfect and if pushed too far or taken in the wrong way they can really cause problems.
Over the last couple of years I have heard the question asked "are our churches are more like cruise ships or battleships?" In other words, are Christians looking for fun, relaxation, and pleasure while the church staff labors to keep them happy, or are we all serving selflessly a greater good? Do we whine if something isn't to our liking, or are we prepared to endure hardship because my personal comfort-level isn't what is paramount.
You get the picture . . . and in some ways this image isn't too bad. But there is a part of me of cringes anytime Christians start using militaristic analogies. I know there is biblical precedent, but my point is that there is a great danger of being misunderstood - by either those who are believers or those who aren't.
To someone leery of Christianity "battleship-talk" and the language of "spiritual warfare" fits all too easily their perceptions that Christians long to rule over the world and subdue by force nonbelievers. Of course, that's what Muslims want to do, right? Not us! How could anyone think that about Christians? Well, just listen to us sometimes . . .
Perhaps a way to modify the analogy is to ask whether being a church together with others is like "being on a cruise ship or on a hospital ship?" We keep the contrast of "here to be served and made happy" versus "here to serve unselfishly" without appearing like crusaders.